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Afkhami M. Neurobiology of egg-laying behavior in Drosophila: neural control of the female reproductive system. J Neurogenet 2024:1-15. [PMID: 39250036 DOI: 10.1080/01677063.2024.2396352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 08/20/2024] [Indexed: 09/10/2024]
Abstract
Egg-laying is one of the key aspects of female reproductive behavior in insects. Egg-laying has been studied since the dawn of Drosophila melanogaster as a model organism. The female's internal state, hormones, and external factors, such as nutrition, light, and social environment, affect egg-laying output. However, only recently, neurobiological features of egg-laying behavior have been studied in detail. fruitless and doublesex, two key players in the sex determination pathway, have become focal points in identifying neurons of reproductive significance in both central and peripheral nervous systems. The reproductive tract and external terminalia house sensory neurons that carry the sensory information of egg maturation, mating and egg-laying. These sensory signals include the presence of male accessory gland products and mechanical stimuli. The abdominal neuromere houses neurons that receive information from the reproductive tract, including sex peptide abdominal ganglion neurons (SAGs), and send their information to the brain. In the brain, neuronal groups like aDNs and pC1 clusters modulate egg-laying decision-making, and other neurons like oviINs and oviDNs are necessary for egg-laying itself. Lastly, motor neurons involved in egg-laying, which are mostly octopaminergic, reside in the abdominal neuromere and orchestrate the muscle movements required for laying the egg. Egg-laying neuronal control is important in various evolutionary processes like cryptic female choice, and using different Drosophila species can provide intriguing avenues for the future of the field.
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Affiliation(s)
- Mehrnaz Afkhami
- School of Biological Sciences, University of Oklahoma, Norman, OK, USA
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2
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Hu H, Tan D, Luo T, Tong X, Han M, Shen J, Dai F. Cyclin B3 plays pleiotropic roles in female reproductive organogenesis and early embryogenesis in the silkworm, Bombyx mori. PEST MANAGEMENT SCIENCE 2024; 80:376-387. [PMID: 37698372 DOI: 10.1002/ps.7767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 08/22/2023] [Accepted: 09/12/2023] [Indexed: 09/13/2023]
Abstract
BACKGROUND The reproductive system plays a crucial role in insect survival, reproduction and species specificity. Understanding the molecular mechanisms underlying reproductive organogenesis contributes to improving the efficiency of sterile insect technique marked by an eco-friendly pest management strategy. Lepidoptera is one of the largest orders of insects, most of which are major pests in agriculture and forestry. Our study aimed to screen the genes responsible for reproductive organogenesis and unravel the mechanism underlying female reproductive organ defects. RESULTS Morphological investigation of female reproductive organs showed a defective connection between oviductus geminus and oviductus communis on the second day of pupa (P2) in Speckled mutant silkworm. RNA_Seq identified a total of 18 049 transcripts that were expressed in the P2 female internal reproductive organs without ovary in Spc/+ compared to +Spc /+Spc . Differential expression analysis identified 312 up-regulated genes and 221 down-regulated genes in Spc/+. KEGG analysis identified 44 significantly enriched pathways. The results of qRT-PCR performed on 33 genes significantly matched the outcomes of the RNA_Seq. Dysfunction of Cyclin B3 resulted in a defective connection of the oviductus communis with the ovariole, dysfunction of oogenesis, and a petite body. Moreover, homozygous recessive lethality of Cyclin B3/Cyclin B3 occurred during early embryogenesis. CONCLUSION Our results suggest that Cyclin B3 is a pleiotropic functional gene that regulates early embryogenesis, oogenesis, development, and female reproductive organogenesis. These results showed that Cyclin B3 has significant effects on lepidopteran mortality, growth, and reproductive physiology, which might be considered a novel and potentially eco-friendly target for lepidopteran pest management. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Hai Hu
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, Southwest University, Chongqing, China
- College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
| | - Duan Tan
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, Southwest University, Chongqing, China
- College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
| | - Tianfu Luo
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, Southwest University, Chongqing, China
| | - Xiaoling Tong
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, Southwest University, Chongqing, China
| | - Minjin Han
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, Southwest University, Chongqing, China
| | - Jianghong Shen
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, Southwest University, Chongqing, China
| | - Fangyin Dai
- State Key Laboratory of Resource Insects, Southwest University, Chongqing, China
- Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, Southwest University, Chongqing, China
- College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
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3
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McQueen EW, Afkhami M, Atallah J, Belote JM, Gompel N, Heifetz Y, Kamimura Y, Kornhauser SC, Masly JP, O’Grady P, Peláez J, Rebeiz M, Rice G, Sánchez-Herrero E, Santos Nunes MD, Santos Rampasso A, Schnakenberg SL, Siegal ML, Takahashi A, Tanaka KM, Turetzek N, Zelinger E, Courtier-Orgogozo V, Toda MJ, Wolfner MF, Yassin A. A standardized nomenclature and atlas of the female terminalia of Drosophila melanogaster. Fly (Austin) 2022; 16:128-151. [PMID: 35575031 PMCID: PMC9116418 DOI: 10.1080/19336934.2022.2058309] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The model organism Drosophila melanogaster has become a focal system for investigations of rapidly evolving genital morphology as well as the development and functions of insect reproductive structures. To follow up on a previous paper outlining unifying terminology for the structures of the male terminalia in this species, we offer here a detailed description of the female terminalia of D. melanogaster. Informative diagrams and micrographs are presented to provide a comprehensive overview of the external and internal reproductive structures of females. We propose a collection of terms and definitions to standardize the terminology associated with the female terminalia in D. melanogaster and we provide a correspondence table with the terms previously used. Unifying terminology for both males and females in this species will help to facilitate communication between various disciplines, as well as aid in synthesizing research across publications within a discipline that has historically focused principally on male features. Our efforts to refine and standardize the terminology should expand the utility of this important model system for addressing questions related to the development and evolution of animal genitalia, and morphology in general.
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Affiliation(s)
- Eden W. McQueen
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Mehrnaz Afkhami
- Department of Biology, University of Oklahoma, Norman, OK, USA
| | - Joel Atallah
- Department of Biological Sciences, University of New Orleans, New Orleans, LA, USA
| | - John M. Belote
- Department of Biology, Syracuse University, Syracuse, NY, USA
| | - Nicolas Gompel
- Evolutionary Ecology, Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Planegg-Martinsried, Germany
| | - Yael Heifetz
- Department of Entomology, The Hebrew University of Jerusalem, Rehovot, Israel
| | | | - Shani C. Kornhauser
- Department of Entomology, The Hebrew University of Jerusalem, Rehovot, Israel
- Biozentrum, University of Basel, Basel, Switzerland
| | - John P. Masly
- Department of Biology, University of Oklahoma, Norman, OK, USA
| | - Patrick O’Grady
- Department of Entomology, Cornell University, Ithaca, NY, USA
| | - Julianne Peláez
- Department of Integrative Biology, University of California, Berkeley, CA, USA
| | - Mark Rebeiz
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Gavin Rice
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ernesto Sánchez-Herrero
- Centro de Biología Molecular Severo Ochoa (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, Cantoblanco, Spain
| | | | | | - Sandra L. Schnakenberg
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, USA
- Sema4, Stamford, CT, USA
| | - Mark L. Siegal
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, USA
| | - Aya Takahashi
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Japan
- Research Center for Genomics and Bioinformatics, Tokyo Metropolitan University, Hachioji, Japan
| | - Kentaro M. Tanaka
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Japan
| | - Natascha Turetzek
- Evolutionary Ecology, Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Planegg-Martinsried, Germany
| | - Einat Zelinger
- Department of Entomology, The Hebrew University of Jerusalem, Rehovot, Israel
- Center for Scientific Imaging, The Hebrew University of Jerusalem, Rehovot, Israel
| | | | | | - Mariana F. Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Amir Yassin
- Laboratoire Evolution, Génomes, Comportement, Ecologie (EGCE), UMR 9191, CNRS, IRD, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
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4
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Wang Y, Rensink AH, Fricke U, Riddle MC, Trent C, van de Zande L, Verhulst EC. Doublesex regulates male-specific differentiation during distinct developmental time windows in a parasitoid wasp. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2022; 142:103724. [PMID: 35093500 DOI: 10.1016/j.ibmb.2022.103724] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 01/19/2022] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
Sexually dimorphic traits in insects are subject to sexual selection, but our knowledge of the underlying molecular mechanisms is still scarce. Here we investigate how the highly conserved gene, Doublesex (Dsx), is involved in shaping sexual dimorphism in the model parasitoid wasp Nasonia vitripennis (Hymenoptera: Pteromalidae). First, we present the revised Dsx gene structure including an alternative transcription start, and two additional male NvDsx transcript isoforms. We show sex-specific NvDsx expression and splicing throughout development, and demonstrate that transient NvDsx silencing in different male developmental stages shifts two sexually dimorphic traits from male to female morphology, with the effect being dependent on the timing of silencing. In addition, we determined the effect of NvDsx on the development of reproductive organs. Transient silencing of NvDsx in early male larvae affects the growth and differentiation of the internal and external reproductive tissues. We did not observe phenotypic changes in females after NvDsx silencing. Our results indicate that male NvDsx is required to suppress female-specific traits and/or to promote male-specific traits during distinct developmental windows. This provides new insights into the regulatory activity of Dsx during male wasp development in the Hymenoptera.
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Affiliation(s)
- Yidong Wang
- Wageningen University, Laboratory of Entomology, Wageningen, the Netherlands
| | - Anna H Rensink
- Evolutionary Genetics, Development and Behaviour, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
| | - Ute Fricke
- Wageningen University, Laboratory of Entomology, Wageningen, the Netherlands
| | - Megan C Riddle
- Biology Department, Western Washington University, Washington, USA
| | - Carol Trent
- Biology Department, Western Washington University, Washington, USA
| | - Louis van de Zande
- Evolutionary Genetics, Development and Behaviour, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
| | - Eveline C Verhulst
- Wageningen University, Laboratory of Entomology, Wageningen, the Netherlands; Wageningen University, Laboratory of Genetics, Wageningen, the Netherlands.
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5
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Kato Y, Sawada A, Tonai K, Tatsuno H, Uenoyama T, Itoh M. A new allele of <i>engrailed</i>, <i>en<sup>NK14</sup></i>, causes supernumerary spermathecae in <i>Drosophila melanogaster</i>. Genes Genet Syst 2021; 96:259-269. [DOI: 10.1266/ggs.21-00030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- Yasuko Kato
- Department of Applied Biology, Kyoto Institute of Technology
| | - Akiko Sawada
- Department of Applied Biology, Kyoto Institute of Technology
| | - Kazuki Tonai
- Department of Applied Biology, Kyoto Institute of Technology
| | - Hisashi Tatsuno
- Department of Applied Biology, Kyoto Institute of Technology
| | | | - Masanobu Itoh
- Advanced Insect Research Promotion Center, Kyoto Institute of Technology
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6
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Interplay between sex determination cascade and major signaling pathways during Drosophila eye development: Perspectives for future research. Dev Biol 2021; 476:41-52. [PMID: 33745943 DOI: 10.1016/j.ydbio.2021.03.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 02/07/2021] [Accepted: 03/01/2021] [Indexed: 12/15/2022]
Abstract
Understanding molecular mechanisms of sexually dimorphic organ growth is a fundamental problem of developmental biology. Recent quantitative studies showed that the Drosophila compound eye is a convenient model to study the determination of the final organ size. In Drosophila, females have larger eyes than males and this is evident even after correction for the larger body size. Moreover, female eyes include more ommatidia (photosensitive units) than male eyes and this difference is specified at the third larval instar in the eye primordia called eye imaginal discs. This may result in different visual capabilities between the two sexes and have behavioral consequences. Despite growing evidence on the genetic bases of eye size variation between different Drosophila species and strains, mechanisms responsible for within-species sexual dimorphism still remain elusive. Here, we discuss a presumptive crosstalk between the sex determination cascade and major signaling pathways during dimorphic eye development. Male- and female-specific isoforms of Doublesex (Dsx) protein are known to control sex-specific differentiation in the somatic tissues. However, no data on Dsx function during eye disc growth and patterning are currently available. Remarkably, Sex lethal (Sxl), the sex determination switch protein, was shown to directly affect Hedgehog (Hh) and Notch (N) signaling in the Drosophila wing disc. The similarity of signaling pathways involved in the wing and eye disc growth suggests that Sxl might be integrated into regulation of eye development. Dsx role in the eye disc requires further investigation. We discuss currently available data on sex-biased gene expression in the Drosophila eye and highlight perspectives for future studies.
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7
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Zeitz C, Nassisi M, Laurent-Coriat C, Andrieu C, Boyard F, Condroyer C, Démontant V, Antonio A, Lancelot ME, Frederiksen H, Kloeckener-Gruissem B, El-Shamieh S, Zanlonghi X, Meunier I, Roux AF, Mohand-Saïd S, Sahel JA, Audo I. CHM mutation spectrum and disease: An update at the time of human therapeutic trials. Hum Mutat 2021; 42:323-341. [PMID: 33538369 DOI: 10.1002/humu.24174] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 12/21/2020] [Accepted: 01/20/2021] [Indexed: 12/15/2022]
Abstract
Choroideremia is an X-linked inherited retinal disorder (IRD) characterized by the degeneration of retinal pigment epithelium, photoreceptors, choriocapillaris and choroid affecting males with variable phenotypes in female carriers. Unlike other IRD, characterized by a large clinical and genetic heterogeneity, choroideremia shows a specific phenotype with causative mutations in only one gene, CHM. Ongoing gene replacement trials raise further interests in this disorder. We describe here the clinical and genetic data from a French cohort of 45 families, 25 of which carry novel variants, in the context of 822 previously reported choroideremia families. Most of the variants represent loss-of-function mutations with eleven families having large (i.e. ≥6 kb) genomic deletions, 18 small insertions, deletions or insertion deletions, six showing nonsense variants, eight splice site variants and two missense variants likely to affect splicing. Similarly, 822 previously published families carry mostly loss-of-function variants. Recurrent variants are observed worldwide, some of which linked to a common ancestor, others arisen independently in specific CHM regions prone to mutations. Since all exons of CHM may harbor variants, Sanger sequencing combined with quantitative polymerase chain reaction or multiplex ligation-dependent probe amplification experiments are efficient to achieve the molecular diagnosis in patients with typical choroideremia features.
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Affiliation(s)
- Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Marco Nassisi
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Camille Andrieu
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC1423, Paris, France
| | - Fiona Boyard
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Vanessa Démontant
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Aline Antonio
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Helen Frederiksen
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Barbara Kloeckener-Gruissem
- Institute of Medical Molecular Genetics, University of Zurich, Schlieren, Switzerland.,Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Said El-Shamieh
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,Department of Medical Laboratory Technology, Faculty of Health Sciences, Beirut Arab University, Beirut, Lebanon
| | - Xavier Zanlonghi
- Clinique Pluridisciplinaire Jules Verne, Institut Ophtalmologique de l'Ouest, Nantes, France
| | - Isabelle Meunier
- National Reference Centre for Inherited Sensory Diseases, University of Montpellier, Montpellier University Hospital, Montpellier, France.,Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
| | - Anne-Françoise Roux
- Laboratoire de Génétique Moléculaire, CHU de Montpellier, Université de Montpellier, Montpellier, France
| | - Saddek Mohand-Saïd
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC1423, Paris, France
| | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC1423, Paris, France.,Fondation Ophtalmologique Adolphe de Rothschild, Paris, France.,Académie des Sciences-Institut de France, Paris, France.,Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC1423, Paris, France.,Department of Genetics, UCL-Institute of Ophthalmology, London, UK
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8
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Nomura S, Fujisawa T, Sota T. Gene expression during genital morphogenesis in the ground beetle Carabus maiyasanus. INSECT SCIENCE 2020; 27:975-986. [PMID: 31318143 DOI: 10.1111/1744-7917.12712] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/01/2019] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
To investigate the developmental genetics of genital formation in the carabid beetle Carabus maiyasanus, we compared gene expression patterns among five stages using transcriptomic RNA sequencing data from abdominal segments and genitalia in the third (last) larval instar (including prepupa) and pupal stages. We identified 18 839 genes, of which 10 796 were differentially expressed among stages or between sexes. There were relatively few differentially expressed genes (DEGs) between the sexes (3%). The DEGs were clustered into six groups, mainly according to stage-specific expression patterns. Genes in clusters 1-3 showed high expression levels before pupation and low expression levels during the pupal period, whereas genes in clusters 4-6 showed high expression levels from the prepupal to the pupal stages. Genes related to the initial pupation process and differentiation of genital discs in Drosophila were involved in clusters 4 and 6 and showed low expression levels at early third instar and elevated expression levels from the early prepupal stage, suggesting that the pupation process and genital differentiation started in the prepupal stage. Clusters 4 and 5 included developmental genes related to organ size control, which may be important in the formation of internal genital structures during the pupal stage.
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Affiliation(s)
- Shota Nomura
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto, Japan
| | - Tomochika Fujisawa
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto, Japan
| | - Teiji Sota
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto, Japan
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9
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An Atlas of Transcription Factors Expressed in Male Pupal Terminalia of Drosophila melanogaster. G3-GENES GENOMES GENETICS 2019; 9:3961-3972. [PMID: 31619460 PMCID: PMC6893207 DOI: 10.1534/g3.119.400788] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
During development, transcription factors and signaling molecules govern gene regulatory networks to direct the formation of unique morphologies. As changes in gene regulatory networks are often implicated in morphological evolution, mapping transcription factor landscapes is important, especially in tissues that undergo rapid evolutionary change. The terminalia (genital and anal structures) of Drosophila melanogaster and its close relatives exhibit dramatic changes in morphology between species. While previous studies have identified network components important for patterning the larval genital disc, the networks governing adult structures during pupal development have remained uncharted. Here, we performed RNA-seq in whole Drosophila melanogaster male terminalia followed by in situ hybridization for 100 highly expressed transcription factors during pupal development. We find that the male terminalia are highly patterned during pupal stages and that specific transcription factors mark separate structures and substructures. Our results are housed online in a searchable database (https://flyterminalia.pitt.edu/) as a resource for the community. This work lays a foundation for future investigations into the gene regulatory networks governing the development and evolution of Drosophila terminalia.
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10
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Cooperation of axial and sex specific information controls Drosophila female genitalia growth by regulating the Decapentaplegic pathway. Dev Biol 2019; 454:145-155. [DOI: 10.1016/j.ydbio.2019.06.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/18/2019] [Accepted: 06/20/2019] [Indexed: 01/18/2023]
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11
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Rice GR, Barmina O, Luecke D, Hu K, Arbeitman M, Kopp A. Modular tissue-specific regulation of doublesex underpins sexually dimorphic development in Drosophila. Development 2019; 146:dev178285. [PMID: 31285355 PMCID: PMC6679366 DOI: 10.1242/dev.178285] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 06/28/2019] [Indexed: 11/20/2022]
Abstract
The ability of a single genome to produce distinct and often dramatically different male and female forms is one of the wonders of animal development. In Drosophila melanogaster, most sexually dimorphic traits are controlled by sex-specific isoforms of the doublesex (dsx) transcription factor, and dsx expression is mostly limited to cells that give rise to sexually dimorphic traits. However, it is unknown how this mosaic of sexually dimorphic and monomorphic organs arises. Here, we characterize the cis-regulatory sequences that control dsx expression in the foreleg, which contains multiple types of sex-specific sensory organs. We find that separate modular enhancers are responsible for dsx expression in each sexually dimorphic organ. Expression of dsx in the sex comb is co-regulated by two enhancers with distinct spatial and temporal specificities that are separated by a genitalia-specific enhancer. The sex comb-specific enhancer from D. willistoni, a species that primitively lacks sex combs, is not active in the foreleg. Thus, the mosaic of sexually dimorphic and monomorphic organs depends on modular regulation of dsx transcription by dedicated cell type-specific enhancers.
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Affiliation(s)
- Gavin R Rice
- Department of Evolution and Ecology, University of California-Davis, Davis, CA 95616, USA
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Olga Barmina
- Department of Evolution and Ecology, University of California-Davis, Davis, CA 95616, USA
| | - David Luecke
- Department of Evolution and Ecology, University of California-Davis, Davis, CA 95616, USA
| | - Kevin Hu
- Department of Evolution and Ecology, University of California-Davis, Davis, CA 95616, USA
| | - Michelle Arbeitman
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL 32306, USA
| | - Artyom Kopp
- Department of Evolution and Ecology, University of California-Davis, Davis, CA 95616, USA
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12
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Camara N, Whitworth C, Dove A, Van Doren M. Doublesex controls specification and maintenance of the gonad stem cell niches in Drosophila. Development 2019; 146:dev.170001. [PMID: 31043421 DOI: 10.1242/dev.170001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 04/23/2019] [Indexed: 11/20/2022]
Abstract
Sex-specific development of the gonads is a key aspect of sexual dimorphism that is regulated by Doublesex/Mab3-related transcription factors (DMRTs) in diverse animal species. We find that in mutants for Drosophila dsx, important components of the male and female gonad stem cell niches (hubs and terminal filaments/cap cells, respectively) still form. Initially, gonads in all dsx mutants (both XX and XY) initiate the male program of development, but later half of these gonads switch to form female stem cell niche structures. One individual can have both male-type and female-type gonad niches; however, male and female niches are usually not observed in the same gonad, indicating that cells make a 'group decision' about which program to follow. We conclude that dsx does not act in an instructive manner to regulate male versus female niche formation, as these structures form in the absence of dsx function. Instead, dsx acts to 'tip the balance' between the male or female programs, which are then executed independently of dsx We show that bric a brac acts downstream of dsx to control the male versus female niche decision. These results indicate that, in both flies and mammals, the sexual fate of the somatic gonad is remarkably plastic and is controlled by a combination of autonomous and non-autonomous cues.
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Affiliation(s)
- Nicole Camara
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Cale Whitworth
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Abigail Dove
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Mark Van Doren
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
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Andrew DJ, Chen EH, Manoli DS, Ryner LC, Arbeitman MN. Sex and the Single Fly: A Perspective on the Career of Bruce S. Baker. Genetics 2019; 212:365-376. [PMID: 31167898 PMCID: PMC6553822 DOI: 10.1534/genetics.119.301928] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 04/01/2019] [Indexed: 11/18/2022] Open
Abstract
Bruce Baker, a preeminent Drosophila geneticist who made fundamental contributions to our understanding of the molecular genetic basis of sex differences, passed away July 1, 2018 at the age of 72. Members of Bruce's laboratory remember him as an intensely dedicated, rigorous, creative, deep-thinking, and fearless scientist. His trainees also remember his strong commitment to teaching students at every level. Bruce's career studying sex differences had three major epochs, where the laboratory was focused on: (1) sex determination and dosage compensation, (2) the development of sex-specific structures, and (3) the molecular genetic basis for sex differences in behavior. Several members of the Baker laboratory have come together to honor Bruce by highlighting some of the laboratory's major scientific contributions in these areas.
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Affiliation(s)
- Deborah J Andrew
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Elizabeth H Chen
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
- Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Devanand S Manoli
- Department of Psychiatry, University of California, San Francisco, California 94158
- Weill Institute for Neuroscience, Center for Integrative Neuroscience, University of California, San Francisco, California 94158
| | - Lisa C Ryner
- Development Sciences Division, Roche Genentech, South San Francisco, California 94080
| | - Michelle N Arbeitman
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, Florida 32306
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14
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Li X, Jin B, Dong Y, Chen X, Tu Z, Gu J. Two of the three Transformer-2 genes are required for ovarian development in Aedes albopictus. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 109:92-105. [PMID: 30914323 PMCID: PMC6636634 DOI: 10.1016/j.ibmb.2019.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 03/18/2019] [Accepted: 03/21/2019] [Indexed: 05/23/2023]
Abstract
In Drosophila melanogaster, transformer-2 (tra2) plays an essential role in the sex-specific splicing of doublesex (dsx) and fruitless (fru), two key transcription factor genes that program sexual differentiation and regulate sexual behavior. In the present study, the sequences and expression profiles of three tra2 (Aalbtra2) genes in the Asian tiger mosquito, Aedes albopictus (Ae. albopictus) were characterized. Phylogenetic analysis revealed that these paralogs resulted from two duplication events. The first occurred in the common ancestor of Culicidae, giving rise to the tra2-α and tra2-β clades that are found across divergent mosquito genera, including Aedes, Culex, and Anopheles. The second occurred within the tra2-α clade, giving rise to tra2-γ in Ae. albopictus. In addition to the conserved RNA recognition motif (RRM), arginine-rich/serine-rich regions (RS domains) and a linker region, a glycine-rich region located between the RRM and RS2 was observed in Tra2-α and Tra2-γ of Ae. albopictus that has not yet been described in the Tra2 proteins of dipteran insects. Quantitative real-time PCR detected relatively high levels of transcripts from all three tra2 paralogs in 0-2 h embryos, suggesting maternal deposition of these transcripts. All three Aalbtra2 genes were highly expressed in the ovary, while Aalbtra2-β was also highly expressed in the testis. RNAi-mediated knockdown of any or all Aalbtra2 genes did not result in an obvious switch of the sex-specificity in dsx and fru splicing in the whole-body samples. However, knockdown of transcripts from all three tra2 genes significantly reduced the female isoform of dsx mRNA and increased the male isoform of the dsx mRNA in both the ovary and the fat body in adult females. Furthermore, knockdown of either Aalbtra2-α or Aalbtra2-γ or all three Aalbtra2 led to a decrease in ovariole number and ovary size after a blood meal. Taken together, these results indicate that two of the three tra2 genes affect female ovarian development.
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Affiliation(s)
- Xiaocong Li
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Binbin Jin
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Yunqiao Dong
- Reproductive Medical Centre of Guangdong Women and Children Hospital, Guangzhou, Guangdong, 511442, China
| | - Xiaoguang Chen
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, 510515, China.
| | - Zhijian Tu
- Department of Biochemistry, Virginia Tech, Blacksburg, VA, 24060, USA
| | - Jinbao Gu
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, 510515, China.
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15
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Morita S, Ando T, Maeno A, Mizutani T, Mase M, Shigenobu S, Niimi T. Precise staging of beetle horn formation in Trypoxylus dichotomus reveals the pleiotropic roles of doublesex depending on the spatiotemporal developmental contexts. PLoS Genet 2019; 15:e1008063. [PMID: 30969957 PMCID: PMC6457530 DOI: 10.1371/journal.pgen.1008063] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 03/03/2019] [Indexed: 11/19/2022] Open
Abstract
Many scarab beetles have sexually dimorphic exaggerated horns that are an evolutionary novelty. Since the shape, number, size, and location of horns are highly diverged within Scarabaeidae, beetle horns are an attractive model for studying the evolution of sexually dimorphic and novel traits. In beetles including the Japanese rhinoceros beetle Trypoxylus dichotomus, the sex differentiation gene doublesex (dsx) plays a crucial role in sexually dimorphic horn formation during larval-pupal development. However, knowledge of when and how dsx drives the gene regulatory network (GRN) for horn formation to form sexually dimorphic horns during development remains elusive. To address this issue, we identified a Trypoxylus-ortholog of the sex determination gene, transformer (tra), that regulates sex-specific splicing of the dsx pre-mRNA, and whose loss of function results in sex transformation. By knocking down tra function at multiple developmental timepoints during larval-pupal development, we estimated the onset when the sex-specific GRN for horn formation is driven. In addition, we also revealed that dsx regulates different aspects of morphogenetic activities during the prepupal and pupal developmental stages to form appropriate morphologies of pupal head and thoracic horn primordia as well as those of adult horns. Based on these findings, we discuss the evolutionary developmental background of sexually dimorphic trait growth in horned beetles. Beetles in the family Scarabaeidae have various types of horns on their heads and thoraces, and the shape, size, number, and location of these horns are highly diversified within the group. In addition, many scarab beetle horns are sexually dimorphic. The acquisition of these evolutionarily novel horns, and the mechanisms for the diversification of these structures is an interesting question. To address this question, we focused on the rhinoceros beetle Tripoxylus dichotomus. Here we identified the exact developmental timepoints during which the morphological sexual dimorphism of horn primordia appears, estimated the onset of the developmental program for sexually dimorphic horn formation driven by doublesex, and revealed that doublesex regulates different aspects of cell activities during horn formation depending on particular spatiotemporal developmental contexts. Our study provides insights into regulatory shifts in these mechanisms during the evolution of sexually dimorphic traits in horned beetles.
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Affiliation(s)
- Shinichi Morita
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Toshiya Ando
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Akiteru Maeno
- Mammalian Genetics Laboratory, Genetic Strains Research Center, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Takeshi Mizutani
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Mutsuki Mase
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
| | - Shuji Shigenobu
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki, Japan
- NIBB Core Research Facilities, National Institute for Basic Biology, 38 Nishigonaka Myodaiji, Okazaki, Japan
| | - Teruyuki Niimi
- Division of Evolutionary Developmental Biology, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 38 Nishigonaka, Myodaiji, Okazaki, Japan
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan
- * E-mail:
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16
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Rice G, David JR, Kamimura Y, Masly JP, Mcgregor AP, Nagy O, Noselli S, Nunes MDS, O’Grady P, Sánchez-Herrero E, Siegal ML, Toda MJ, Rebeiz M, Courtier-Orgogozo V, Yassin A. A standardized nomenclature and atlas of the male terminalia of Drosophila melanogaster. Fly (Austin) 2019; 13:51-64. [PMID: 31401934 PMCID: PMC6988887 DOI: 10.1080/19336934.2019.1653733] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 07/26/2019] [Accepted: 08/04/2019] [Indexed: 10/26/2022] Open
Abstract
Animal terminalia represent some of the most diverse and rapidly evolving structures in the animal kingdom, and for this reason have been a mainstay in the taxonomic description of species. The terminalia of Drosophila melanogaster, with its wide range of experimental tools, have recently become the focus of increased interest in the fields of development, evolution, and behavior. However, studies from different disciplines have often used discrepant terminologies for the same anatomical structures. Consequently, the terminology of genital parts has become a barrier to integrating results from different fields, rendering it difficult to determine what parts are being referenced. We formed a consortium of researchers studying the genitalia of D. melanogaster to help establish a set of naming conventions. Here, we present a detailed visual anatomy of male genital parts, including a list of synonymous terms, and suggest practices to avoid confusion when referring to anatomical parts in future studies. The goal of this effort is to facilitate interdisciplinary communication and help newcomers orient themselves within the exciting field of Drosophila genitalia.
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Affiliation(s)
- Gavin Rice
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jean R. David
- Laboratoire Evolution, Génomes, Comportement, Ecologie (EGCE), UMR 9191, CNRS,IRD, Univ.Paris-Sud, Université Paris-Saclay, cedex, France
| | | | - John P. Masly
- Department of Biology, University of Oklahoma, Norman, OK, USA
| | - Alistair P. Mcgregor
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
| | - Olga Nagy
- CNRS UMR7592, Institut Jacques Monod, Université de Paris, Paris, France
| | | | | | - Patrick O’Grady
- Department of Entomology, Cornell University, Ithaca, NY, USA
| | - Ernesto Sánchez-Herrero
- Centro de Biología Molecular Severo Ochoa (C.S.I.C.-U.A.M.), Universidad Autónoma de Madrid, Cantoblanco, Spain
| | - Mark L. Siegal
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, USA
| | | | - Mark Rebeiz
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | | | - Amir Yassin
- Institut de Systématique, Evolution et Biodiversité, UMR7205, Centre National de la Recherche Scientifique, MNHN, Sorbonne Université, EPHE, Université des Antilles, Paris, France
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17
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Millington JW, Rideout EJ. Sex differences in Drosophila development and physiology. CURRENT OPINION IN PHYSIOLOGY 2018. [DOI: 10.1016/j.cophys.2018.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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18
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Trost M, Blattner AC, Leo S, Lehner CF. Drosophila dany is essential for transcriptional control and nuclear architecture in spermatocytes. Development 2017; 143:2664-76. [PMID: 27436041 DOI: 10.1242/dev.134759] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/03/2016] [Indexed: 01/14/2023]
Abstract
The terminal differentiation of adult stem cell progeny depends on transcriptional control. A dramatic change in gene expression programs accompanies the transition from proliferating spermatogonia to postmitotic spermatocytes, which prepare for meiosis and subsequent spermiogenesis. More than a thousand spermatocyte-specific genes are transcriptionally activated in early Drosophila spermatocytes. Here we describe the identification and initial characterization of dany, a gene required in spermatocytes for the large-scale change in gene expression. Similar to tMAC and tTAFs, the known major activators of spermatocyte-specific genes, dany has a recent evolutionary origin, but it functions independently. Like dan and danr, its primordial relatives with functions in somatic tissues, dany encodes a nuclear Psq domain protein. Dany associates preferentially with euchromatic genome regions. In dany mutant spermatocytes, activation of spermatocyte-specific genes and silencing of non-spermatocyte-specific genes are severely compromised and the chromatin no longer associates intimately with the nuclear envelope. Therefore, as suggested recently for Dan/Danr, we propose that Dany is essential for the coordination of change in cell type-specific expression programs and large-scale spatial chromatin reorganization.
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Affiliation(s)
- Martina Trost
- Institute of Molecular Life Sciences (IMLS), University of Zurich, Zurich 8057, Switzerland
| | - Ariane C Blattner
- Institute of Molecular Life Sciences (IMLS), University of Zurich, Zurich 8057, Switzerland
| | - Stefano Leo
- Institute of Molecular Life Sciences (IMLS), University of Zurich, Zurich 8057, Switzerland
| | - Christian F Lehner
- Institute of Molecular Life Sciences (IMLS), University of Zurich, Zurich 8057, Switzerland
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19
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Uechi H, Kuranaga E. Mechanisms of collective cell movement lacking a leading or free front edge in vivo. Cell Mol Life Sci 2017; 74:2709-2722. [PMID: 28243700 PMCID: PMC11107506 DOI: 10.1007/s00018-017-2489-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 02/09/2017] [Accepted: 02/13/2017] [Indexed: 12/15/2022]
Abstract
Collective cell movement is one of the strategies for achieving the complex shapes of tissues and organs. In this process, multiple cells within a group held together by cell-cell adhesion acquire mobility and move together in the same direction. In some well-studied models of collective cell movement, the mobility depends strongly on traction generated at the leading edge by cells located at the front. However, recent advances in live-imaging techniques have led to the discovery of other types of collective cell movement lacking a leading edge or even a free edge at the front, in a diverse array of morphological events, including tubule elongation, epithelial sheet extension, and tissue rotation. We herein review some of the developmental events that are organized by collective cell movement and attempt to elucidate the underlying cellular and molecular mechanisms, which include membrane protrusions, guidance cues, cell intercalation, and planer cell polarity, or chirality pathways.
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Affiliation(s)
- Hiroyuki Uechi
- Laboratory for Histogenetic Dynamics, RIKEN Center for Developmental Biology, Kobe, 650-0047, Japan
| | - Erina Kuranaga
- Laboratory for Histogenetic Dynamics, RIKEN Center for Developmental Biology, Kobe, 650-0047, Japan.
- Laboratory of Histogenetic Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai, 980-8578, Japan.
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20
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Dynamic Notch Signaling Specifies Each Cell Fate in Drosophila Spermathecal Lineage. G3-GENES GENOMES GENETICS 2017; 7:1417-1427. [PMID: 28258114 PMCID: PMC5427495 DOI: 10.1534/g3.117.040212] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Spermathecae are glandular organs in the insect female reproductive tract that play essential roles in insect reproduction; however, the molecular mechanism involved in their development is largely unknown. Drosophila spermathecae consist of class-III secretory units, in which each secretory cell (SC) discharges its products to the central lumen through an end-apparatus and a canal. Secretory unit formation in Drosophila spermathecae utilizes a fixed cell lineage, in which each secretory unit precursor (SUP) divides to produce one pIIb cell and one pIIa cell. The former differentiates into an apical cell (AC), whereas the latter divides again to produce an SC and a basal cell (BC). It is unclear how each cell acquires its identity and contributes to secretory unit formation. Here, we demonstrate that Notch signaling is required and sufficient for the specification of lumen epithelial precursors (LEPs; vs. SUPs), pIIb (vs. pIIa), and SCs (vs. BCs) sequentially. To our surprise, Notch activation in LEPs and SCs apparently utilizes different ligand mechanisms. In addition, Notch signaling both suppresses and activates transcription factors Hindsight (Hnt) and Cut during spermathecal lineage specification, supporting the notion that Notch signaling can have opposite biological outcomes in different cellular environments. Furthermore, LEP-derived epithelial cells (ECs) and ACs show distinct cellular morphology and are essential for securing secretory units to the epithelial lumen. Our work demonstrates, for the first time, the dynamic role of Notch signaling in binary cell fate determination in Drosophila spermathecae and the role of ECs and ACs in secretory unit formation.
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21
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Intersex (ix) mutations of Drosophila melanogaster cause nonrandom cell death in genital disc and can induce tumours in genitals in response to decapentaplegic (dpp(disk)) mutations. J Genet 2016; 94:207-20. [PMID: 26174668 DOI: 10.1007/s12041-015-0503-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In Drosophila melanogaster, the intersex (ix) is a terminally positioned gene in somatic sex determination hierarchy and function with the female specific product of double sex (DSX(F)) to implement female sexual differentiation. The null phenotype of ix is to transform diplo-X individuals into intersexes while leaving haplo-X animals unaffected. This study on the effect of different intersex mutations on genital disc development provides the following major results: (i) similar range of a characteristic array of morphological structures (from almost double sex terminalia to extreme reduction of terminal appendages) was displayed by the terminalia of XX ix(1)/ix(1) , XX ix(2)/ix(2) and XX ix(5)/ix(5) individuals; (ii) an increased number of apoptotic cells were found to occur in a localized manner in mature third instar larval genital discs of ix individuals; (iii) ix mutations can induce high frequency of neoplastic tumours in genitals in the presence of decapentaplegic (dpp(disk)) mutations; and (iv) heteroallelic combinations of dpp(disk) mutations can also induce tumours in intersex genitals with variable expressivity. On the basis of these findings, we suggest that: (i) loss of function of ix causes massive cell death in both male and female genital primordia of genital discs, resulting phenotype mimicking in male and female characteristics in genitals; and (ii) at the discs, the apoptotic cells persist as 'undead' cells that can induce oncogenic transformation in the neighbouring disc cells when dpp signalling is blocked or reduced by dpp(disk) mutations.
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22
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Sato K, Hiraiwa T, Maekawa E, Isomura A, Shibata T, Kuranaga E. Left-right asymmetric cell intercalation drives directional collective cell movement in epithelial morphogenesis. Nat Commun 2015; 6:10074. [PMID: 26656655 PMCID: PMC4682055 DOI: 10.1038/ncomms10074] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 10/30/2015] [Indexed: 02/07/2023] Open
Abstract
Morphogenetic epithelial movement occurs during embryogenesis and drives complex tissue formation. However, how epithelial cells coordinate their unidirectional movement while maintaining epithelial integrity is unclear. Here we propose a novel mechanism for collective epithelial cell movement based on Drosophila genitalia rotation, in which epithelial tissue rotates clockwise around the genitalia. We found that this cell movement occurs autonomously and requires myosin II. The moving cells exhibit repeated left–right-biased junction remodelling, while maintaining adhesion with their neighbours, in association with a polarized myosin II distribution. Reducing myosinID, known to cause counter-clockwise epithelial-tissue movement, reverses the myosin II distribution. Numerical simulations revealed that a left–right asymmetry in cell intercalation is sufficient to induce unidirectional cellular movement. The cellular movement direction is also associated with planar cell-shape chirality. These findings support a model in which left–right asymmetric cell intercalation within an epithelial sheet drives collective cellular movement in the same direction. Coordinated epithelial movement during embryogenesis drives complex tissue formation, but how this movement is coordinated to maintain epithelial integrity is not clear. Here the authors show that left-right asymmetry in cell intercalation drives clockwise rotation of epithelia in Drosophila genital development.
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Affiliation(s)
- Katsuhiko Sato
- Laboratory for Physical Biology, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Tetsuya Hiraiwa
- Laboratory for Physical Biology, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Emi Maekawa
- Laboratory for Histogenetic Dynamics, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Ayako Isomura
- Laboratory for Histogenetic Dynamics, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Tatsuo Shibata
- Laboratory for Physical Biology, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Erina Kuranaga
- Laboratory for Histogenetic Dynamics, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan.,Laboratory of Molecular Cell Biology and Development, Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan.,Laboratory for Tissue Development Dynamics, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Nara 630-0192, Japan.,Laboratory for Histogenetic Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
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23
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siRNA-Mediated Silencing of doublesex during Female Development of the Dengue Vector Mosquito Aedes aegypti. PLoS Negl Trop Dis 2015; 9:e0004213. [PMID: 26544686 PMCID: PMC4636264 DOI: 10.1371/journal.pntd.0004213] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/14/2015] [Indexed: 12/30/2022] Open
Abstract
The development of sex-specific traits, including the female-specific ability to bite humans and vector disease, is critical for vector mosquito reproduction and pathogen transmission. Doublesex (Dsx), a terminal transcription factor in the sex determination pathway, is known to regulate sex-specific gene expression during development of the dengue fever vector mosquito Aedes aegypti. Here, the effects of developmental siRNA-mediated dsx silencing were assessed in adult females. Targeting of dsx during A. aegypti development resulted in decreased female wing size, a correlate for body size, which is typically larger in females. siRNA-mediated targeting of dsx also resulted in decreased length of the adult female proboscis. Although dsx silencing did not impact female membrane blood feeding or mating behavior in the laboratory, decreased fecundity and fertility correlated with decreased ovary length, ovariole length, and ovariole number in dsx knockdown females. Dsx silencing also resulted in disruption of olfactory system development, as evidenced by reduced length of the female antenna and maxillary palp and the sensilla present on these structures, as well as disrupted odorant receptor expression. Female lifespan, a critical component of the ability of A. aegypti to transmit pathogens, was also significantly reduced in adult females following developmental targeting of dsx. The results of this investigation demonstrate that silencing of dsx during A. aegypti development disrupts multiple sex-specific morphological, physiological, and behavioral traits of adult females, a number of which are directly or indirectly linked to mosquito reproduction and pathogen transmission. Moreover, the olfactory phenotypes observed connect Dsx to development of the olfactory system, suggesting that A. aegypti will be an excellent system in which to further assess the developmental genetics of sex-specific chemosensation. Only adult female mosquitoes, which require blood meals for reproduction, bite humans and spread diseases. The genes that regulate development of sex-specific traits may therefore represent novel targets for mosquito control. Here, we examine the effects of silencing the sex-determination gene doublesex (dsx) during development of the human disease vector mosquito Aedes aegypti. Targeting of dsx resulted in decreased length of the female wing and proboscis, ovary and reproductive defects, and disruption of olfactory system development. Female lifespan, a critical aspect of mosquito pathogen transmission, was also significantly reduced in adult females following developmental targeting of dsx. The results of this investigation demonstrate that silencing of dsx during A. aegypti development disrupts multiple sex-specific morphological, physiological, and behavioral traits of adult females, a number of which are directly or indirectly linked to mosquito reproduction and pathogen transmission. The results obtained also connect Dsx to development of the mosquito olfactory system, suggesting that A. aegypti will be an excellent system in which to further assess the developmental genetics of sex-specific chemosensation.
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Abstract
Apoptosis is a cellular suicide program, which is on the one hand used to remove superfluous cells thereby promoting tissue or organ morphogenesis. On the other hand, the programmed killing of cells is also critical when potentially harmful cells emerge in a developing or adult organism thereby endangering survival. Due to its critical role apoptosis is tightly controlled, however so far, its regulation on the transcriptional level is less studied and understood. Hox genes, a highly conserved gene family encoding homeodomain transcription factors, have crucial roles in development. One of their prominent functions is to shape animal body plans by eliciting different developmental programs along the anterior-posterior axis. To this end, Hox proteins transcriptionally regulate numerous processes in a coordinated manner, including cell-type specification, differentiation, motility, proliferation as well as apoptosis. In this review, we will focus on how Hox proteins control organismal morphology and function by regulating the apoptotic machinery. We will first focus on well-established paradigms of Hox-apoptosis interactions and summarize how Hox transcription factors control morphological outputs and differentially shape tissues along the anterior-posterior axis by fine-tuning apoptosis in a healthy organism. We will then discuss the consequences when this interaction is disturbed and will conclude with some ideas and concepts emerging from these studies.
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25
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Nipitwattanaphon M, Wang J, Ross KG, Riba-Grognuz O, Wurm Y, Khurewathanakul C, Keller L. Effects of ploidy and sex-locus genotype on gene expression patterns in the fire ant Solenopsis invicta. Proc Biol Sci 2015; 281:rspb.2014.1776. [PMID: 25355475 DOI: 10.1098/rspb.2014.1776] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Males in many animal species differ greatly from females in morphology, physiology and behaviour. Ants, bees and wasps have a haplodiploid mechanism of sex determination whereby unfertilized eggs become males while fertilized eggs become females. However, many species also have a low frequency of diploid males, which are thought to develop from diploid eggs when individuals are homozygous at one or more sex determination loci. Diploid males are morphologically similar to haploids, though often larger and typically sterile. To determine how ploidy level and sex-locus genotype affect gene expression during development, we compared expression patterns between diploid males, haploid males and females (queens) at three developmental timepoints in Solenopsis invicta. In pupae, gene expression profiles of diploid males were very different from those of haploid males but nearly identical to those of queens. An unexpected shift in expression patterns emerged soon after adult eclosion, with diploid male patterns diverging from those of queens to resemble those of haploid males, a pattern retained in older adults. The finding that ploidy level effects on early gene expression override sex effects (including genes implicated in sperm production and pheromone production/perception) may explain diploid male sterility and lack of worker discrimination against them during development.
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Affiliation(s)
- Mingkwan Nipitwattanaphon
- Department of Ecology and Evolution, Biophore, University of Lausanne, 1015 Lausanne, Switzerland Department of Genetics, Faculty of Science, Kasetsart University, Bangkok, Thailand
| | - John Wang
- Department of Ecology and Evolution, Biophore, University of Lausanne, 1015 Lausanne, Switzerland Biodiversity Research Center, Academia Sinica, Nangang Taipei 115, Taiwan, Republic of China
| | - Kenneth G Ross
- Department of Entomology, University of Georgia, Athens, GA 30602, USA
| | - Oksana Riba-Grognuz
- Department of Ecology and Evolution, Biophore, University of Lausanne, 1015 Lausanne, Switzerland Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - Yannick Wurm
- Department of Ecology and Evolution, Biophore, University of Lausanne, 1015 Lausanne, Switzerland Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland School of Biological and Chemical Sciences, Queen Mary University London, London E1 4NS, UK
| | - Chitsanu Khurewathanakul
- Laboratory for High Energy Physics, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Laurent Keller
- Department of Ecology and Evolution, Biophore, University of Lausanne, 1015 Lausanne, Switzerland
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Verhulst EC, van de Zande L. Double nexus--Doublesex is the connecting element in sex determination. Brief Funct Genomics 2015; 14:396-406. [PMID: 25797692 PMCID: PMC4652034 DOI: 10.1093/bfgp/elv005] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
In recent years, our knowledge of the conserved master-switch gene doublesex (dsx) and its function in regulating the development of dimorphic traits in insects has deepened considerably. Here, a comprehensive overview is given on the properties of the male- and female-specific dsx transcripts yielding DSXF and DSXM proteins in Drosophila melanogaster, and the many downstream targets that they regulate. As insects have cell-autonomous sex determination, it was assumed that dsx would be expressed in every somatic cell, but recent research showed that dsx is expressed only when a cell is required to show its sexual identity through function or morphology. This spatiotemporal regulation of dsx expression has not only been established in D. melanogaster but in all insect species studied. Gradually, it has been appreciated that dsx could no longer be viewed as the master-switch gene orchestrating sexual development and behaviour in each cell, but instead should be viewed as the interpreter for the sexual identity of the cell, expressing this identity only on request, making dsx the central nexus of insect sex determination.
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Sex- and tissue-specific functions of Drosophila doublesex transcription factor target genes. Dev Cell 2015; 31:761-73. [PMID: 25535918 DOI: 10.1016/j.devcel.2014.11.021] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 10/02/2014] [Accepted: 11/13/2014] [Indexed: 11/20/2022]
Abstract
Primary sex-determination "switches" evolve rapidly, but Doublesex (DSX)-related transcription factors (DMRTs) act downstream of these switches to control sexual development in most animal species. Drosophila dsx encodes female- and male-specific isoforms (DSX(F) and DSX(M)), but little is known about how dsx controls sexual development, whether DSX(F) and DSX(M) bind different targets, or how DSX proteins direct different outcomes in diverse tissues. We undertook genome-wide analyses to identify DSX targets using in vivo occupancy, binding site prediction, and evolutionary conservation. We find that DSX(F) and DSX(M) bind thousands of the same targets in multiple tissues in both sexes, yet these targets have sex- and tissue-specific functions. Interestingly, DSX targets show considerable overlap with targets identified for mouse DMRT1. DSX targets include transcription factors and signaling pathway components providing for direct and indirect regulation of sex-biased expression.
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Lavine L, Gotoh H, Brent CS, Dworkin I, Emlen DJ. Exaggerated trait growth in insects. ANNUAL REVIEW OF ENTOMOLOGY 2015; 60:453-472. [PMID: 25341090 DOI: 10.1146/annurev-ento-010814-021045] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Animal structures occasionally attain extreme proportions, eclipsing in size the surrounding body parts. We review insect examples of exaggerated traits, such as the mandibles of stag beetles (Lucanidae), the claspers of praying mantids (Mantidae), the elongated hindlimbs of grasshoppers (Orthoptera: Caelifera), and the giant heads of soldier ants (Formicidae) and termites (Isoptera). Developmentally, disproportionate growth can arise through trait-specific modifications to the activity of at least four pathways: the sex determination pathway, the appendage patterning pathway, the insulin/IGF signaling pathway, and the juvenile hormone/ecdysteroid pathway. Although most exaggerated traits have not been studied mechanistically, it is already apparent that distinct developmental mechanisms underlie the evolution of the different types of exaggerated traits. We suggest this reflects the nature of selection in each instance, revealing an exciting link between mechanism, form, and function. We use this information to make explicit predictions for the types of regulatory pathways likely to underlie each type of exaggerated trait.
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Affiliation(s)
- Laura Lavine
- Department of Entomology, Washington State University, Pullman, Washington 99164; ,
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Zhang Y, Liu Y, Li Y, Duan Y, Zhang K, Wang J, Dai Y. Exome sequencing identifies mutations in ABCD1 and DACH2 in two brothers with a distinct phenotype. BMC MEDICAL GENETICS 2014; 15:105. [PMID: 25234129 PMCID: PMC4355004 DOI: 10.1186/s12881-014-0105-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 09/05/2014] [Indexed: 11/18/2022]
Abstract
Background We report on two brothers with a distinct syndromic phenotype and explore the potential pathogenic cause. Methods Cytogenetic tests and exome sequencing were performed on the two brothers and their parents. Variants detected by exome sequencing were validated by Sanger sequencing. Results The main phenotype of the two brothers included congenital language disorder, growth retardation, intellectual disability, difficulty in standing and walking, and urinary and fecal incontinence. To the best of our knowledge, no similar phenotype has been reported previously. No abnormalities were detected by G-banding chromosome analysis or array comparative genomic hybridization. However, exome sequencing revealed novel mutations in the ATP-binding cassette, sub-family D member 1 (ABCD1) and Dachshund homolog 2 (DACH2) genes in both brothers. The ABCD1 mutation was a missense mutation c.1126G > C in exon 3 leading to a p.E376Q substitution. The DACH2 mutation was also a missense mutation c.1069A > T in exon 6, leading to a p.S357C substitution. The mother was an asymptomatic heterozygous carrier. Plasma levels of very-long-chain fatty acids were increased in both brothers, suggesting a diagnosis of adrenoleukodystrophy (ALD); however, their phenotype was not compatible with any reported forms of ALD. DACH2 plays an important role in the regulation of brain and limb development, suggesting that this mutation may be involved in the phenotype of the two brothers. Conclusion The distinct phenotype demonstrated by these two brothers might represent a new form of ALD or a new syndrome. The combination of mutations in ABCD1 and DACH2 provides a plausible mechanism for this phenotype.
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Affiliation(s)
- Yanliang Zhang
- Department of Clinical Laboratory, the First Affiliated Hospital of Kunming Medical University, Yunnan Province, 650032, P R China.
| | - Yanhui Liu
- Prepotency Center, Dongguan Maternal and Child Health Hospital, Guangdong Province, 523000, P R China.
| | - Ya Li
- Department of Clinical Laboratory, the First Affiliated Hospital of Kunming Medical University, Yunnan Province, 650032, P R China.
| | - Yong Duan
- Department of Clinical Laboratory, the First Affiliated Hospital of Kunming Medical University, Yunnan Province, 650032, P R China.
| | - Keyun Zhang
- Radiology Department, Dongguan Guanghua Hospital of Tongji Medical College, Guangdong Province, 523000, P R China.
| | - Junwang Wang
- Radiology Department, Dongguan Guanghua Hospital of Tongji Medical College, Guangdong Province, 523000, P R China.
| | - Yong Dai
- The Clinical Medical Research Center, Second Clinical Medical College (Shenzhen People's Hospital), Jinan University, Guangdong Province, 518020, P R China.
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Mayhew ML, Merritt DJ. The morphogenesis of spermathecae and spermathecal glands in Drosophila melanogaster. ARTHROPOD STRUCTURE & DEVELOPMENT 2013; 42:385-393. [PMID: 23872109 DOI: 10.1016/j.asd.2013.07.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 07/02/2013] [Accepted: 07/03/2013] [Indexed: 06/02/2023]
Abstract
Sperm storage in female insects is important for reproductive success and sperm competition. In Drosophila melanogaster females, sperm viability during storage is dependent upon secretions produced by spermathecae and parovaria. Class III dermal glands are present in both structures. Spermathecal glands are initially comprised of a three-cell unit that is refined to a single secretory cell in the adult. It encapsulates an end-apparatus joining to a cuticular duct passing secretions to the spermathecal lumen. We have examined spermatheca morphogenesis using DIC and fluorescence microscopy. In agreement with a recent study, cell division ceases by 36 h after puparium formation (APF). Immunostaining of the plasma membrane at this stage demonstrates that gland cells wrap around the developing end-apparatus and each other. By 48-60 h APF, the secretory cell exhibits characteristic adult morphology of an enlarged nucleus and extracellular reservoir. A novel finding is the presence of an extracellular reservoir in the basal support cell that is continuous with the secretory cell reservoir. Some indication of early spermathecal gland formation is evident in the division of enlarged cells lying adjacent to the spermathecal lumen at 18 h APF and in cellular processes that bind clusters of cells between 24 and 30 h APF.
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Affiliation(s)
- Mark Leonard Mayhew
- School of Biological Sciences, The University of Queensland, Mansfield Place, Brisbane, Queensland 4072, Australia
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Sun J, Spradling AC. NR5A nuclear receptor Hr39 controls three-cell secretory unit formation in Drosophila female reproductive glands. Curr Biol 2012; 22:862-71. [PMID: 22560612 PMCID: PMC3397175 DOI: 10.1016/j.cub.2012.03.059] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 03/11/2012] [Accepted: 03/13/2012] [Indexed: 12/31/2022]
Abstract
BACKGROUND Secretions within the adult female reproductive tract mediate sperm survival, storage, activation, and selection. Drosophila female reproductive gland secretory cells reside within the adult spermathecae and parovaria, but their development remains poorly characterized. RESULTS With cell-lineage tracing, we found that precursor cells downregulate lozenge and divide stereotypically to generate three-cell secretory units during pupal development. The NR5A-class nuclear hormone receptor Hr39 is essential for precursor cell division and secretory unit formation. Moreover, ectopic Hr39 in multiple tissues generates reproductive gland-like primordia. Rarely, in male genital discs these primordia can develop into sperm-filled testicular spermathecae. CONCLUSION Drosophila spermathecae provide a powerful model for studying gland development. Hr39 functions as a master regulator of a program that may have been conserved throughout animal evolution for the production of female reproductive glands and other secretory tissues.
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Affiliation(s)
| | - Allan C. Spradling
- Corresponding Author: Dr. Allan C. Spradling, Tel. 410-246-3015, Fax. 410-243-6311,
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Siehr MS, Koo PK, Sherlekar AL, Bian X, Bunkers MR, Miller RM, Portman DS, Lints R. Multiple doublesex-related genes specify critical cell fates in a C. elegans male neural circuit. PLoS One 2011; 6:e26811. [PMID: 22069471 PMCID: PMC3206049 DOI: 10.1371/journal.pone.0026811] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 10/04/2011] [Indexed: 11/18/2022] Open
Abstract
Background In most animal species, males and females exhibit differences in behavior and morphology that relate to their respective roles in reproduction. DM (Doublesex/MAB-3) domain transcription factors are phylogenetically conserved regulators of sexual development. They are thought to establish sexual traits by sex-specifically modifying the activity of general developmental programs. However, there are few examples where the details of these interactions are known, particularly in the nervous system. Methodology/Principal Findings In this study, we show that two C. elegans DM domain genes, dmd-3 and mab-23, regulate sensory and muscle cell development in a male neural circuit required for mating. Using genetic approaches, we show that in the circuit sensory neurons, dmd-3 and mab-23 establish the correct pattern of dopaminergic (DA) and cholinergic (ACh) fate. We find that the ETS-domain transcription factor gene ast-1, a non-sex-specific, phylogenetically conserved activator of dopamine biosynthesis gene transcription, is broadly expressed in the circuit sensory neuron population. However, dmd-3 and mab-23 repress its activity in most cells, promoting ACh fate instead. A subset of neurons, preferentially exposed to a TGF-beta ligand, escape this repression because signal transduction pathway activity in these cells blocks dmd-3/mab-23 function, allowing DA fate to be established. Through optogenetic and pharmacological approaches, we show that the sensory and muscle cell characteristics controlled by dmd-3 and mab-23 are crucial for circuit function. Conclusions/Significance In the C. elegans male, DM domain genes dmd-3 and mab-23 regulate expression of cell sub-type characteristics that are critical for mating success. In particular, these factors limit the number of DA neurons in the male nervous system by sex-specifically regulating a phylogenetically conserved dopamine biosynthesis gene transcription factor. Homologous interactions between vertebrate counterparts could regulate sex differences in neuron sub-type populations in the brain.
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Affiliation(s)
- Meagan S. Siehr
- Department of Biology, Texas A & M University, College Station, Texas, United States of America
| | - Pamela K. Koo
- Department of Biology, Texas A & M University, College Station, Texas, United States of America
| | - Amrita L. Sherlekar
- Department of Biology, Texas A & M University, College Station, Texas, United States of America
| | - Xuelin Bian
- Department of Biology, Texas A & M University, College Station, Texas, United States of America
| | - Meredith R. Bunkers
- Department of Biology, Texas A & M University, College Station, Texas, United States of America
| | - Renee M. Miller
- Department of Biomedical Genetics, Center for Neural Development and Disease, University of Rochester, Rochester, New York, United States of America
| | - Douglas S. Portman
- Department of Biomedical Genetics, Center for Neural Development and Disease, University of Rochester, Rochester, New York, United States of America
| | - Robyn Lints
- Department of Biology, Texas A & M University, College Station, Texas, United States of America
- * E-mail:
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Tanaka K, Barmina O, Sanders LE, Arbeitman MN, Kopp A. Evolution of sex-specific traits through changes in HOX-dependent doublesex expression. PLoS Biol 2011; 9:e1001131. [PMID: 21886483 PMCID: PMC3160335 DOI: 10.1371/journal.pbio.1001131] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 07/15/2011] [Indexed: 12/27/2022] Open
Abstract
Almost every animal lineage is characterized by unique sex-specific traits, implying that such traits are gained and lost frequently in evolution. However, the genetic mechanisms responsible for these changes are not understood. In Drosophila, the activity of the sex determination pathway is restricted to sexually dimorphic tissues, suggesting that spatial regulation of this pathway may contribute to the evolution of sex-specific traits. We examine the regulation and function of doublesex (dsx), the main transcriptional effector of the sex determination pathway, in the development and evolution of Drosophila sex combs. Sex combs are a recent evolutionary innovation and show dramatic diversity in the relatively few Drosophila species that have them. We show that dsx expression in the presumptive sex comb region is activated by the HOX gene Sex combs reduced (Scr), and that the male isoform of dsx up-regulates Scr so that both genes become expressed at high levels in this region in males but not in females. Precise spatial regulation of dsx is essential for defining sex comb position and morphology. Comparative analysis of Scr and dsx expression reveals a tight correlation between sex comb morphology and the expression patterns of both genes. In species that primitively lack sex combs, no dsx expression is observed in the homologous region, suggesting that the origin and diversification of this structure were linked to the gain of a new dsx expression domain. Two other, distantly related fly lineages that independently evolved novel male-specific structures show evolutionary gains of dsx expression in the corresponding tissues, where dsx may also be controlled by Scr. These findings suggest that changes in the spatial regulation of sex-determining genes are a key mechanism that enables the evolution of new sex-specific traits, contributing to some of the most dramatic examples of phenotypic diversification in nature.
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Affiliation(s)
- Kohtaro Tanaka
- Department of Evolution and Ecology, University of California–Davis, Davis, California, United States of America
| | - Olga Barmina
- Department of Evolution and Ecology, University of California–Davis, Davis, California, United States of America
| | - Laura E. Sanders
- Section of Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, Los Angeles, California, United States of America
| | - Michelle N. Arbeitman
- Section of Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, Los Angeles, California, United States of America
| | - Artyom Kopp
- Department of Evolution and Ecology, University of California–Davis, Davis, California, United States of America
- * E-mail:
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Abstract
Animals have evolved a bewildering diversity of mechanisms to determine the two sexes. Studies of sex determination genes – their history and function – in non-model insects and Drosophila have allowed us to begin to understand the generation of sex determination diversity. One common theme from these studies is that evolved mechanisms produce activities in either males or females to control a shared gene switch that regulates sexual development. Only a few small-scale changes in existing and duplicated genes are sufficient to generate large differences in sex determination systems. This review summarises recent findings in insects, surveys evidence of how and why sex determination mechanisms can change rapidly and suggests fruitful areas of future research.
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Affiliation(s)
- Tanja Gempe
- Department of Genetics, Heinrich Heine University, Duesseldorf, Universitaetsstrasse 1, Duesseldorf, Germany
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Sexually dimorphic regulation of the Wingless morphogen controls sex-specific segment number in Drosophila. Proc Natl Acad Sci U S A 2011; 108:11139-44. [PMID: 21690416 DOI: 10.1073/pnas.1108431108] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sexual dimorphism is widespread throughout the metazoa and plays important roles in mate recognition and preference, sex-based niche partitioning, and sex-specific coadaptation. One notable example of sex-specific differences in insect body morphology is presented by the higher diptera, such as Drosophila, in which males develop fewer abdominal segments than females. Because diversity in segment number is a distinguishing feature of major arthropod clades, it is of fundamental interest to understand how different numbers of segments can be generated within the same species. Here we show that sex-specific and segment-specific regulation of the Wingless (Wg) morphogen underlies the development of sexually dimorphic adult segment number in Drosophila. Wg expression is repressed in the developing terminal male abdominal segment by the combination of the Hox protein Abdominal-B (Abd-B) and the sex-determination regulator Doublesex (Dsx). The subsequent loss of the terminal male abdominal segment during pupation occurs through a combination of developmental processes including segment compartmental transformation, apoptosis, and suppression of cell proliferation. Furthermore, we show that ectopic expression of Wg is sufficient to rescue this loss. We propose that dimorphic Wg regulation, in concert with monomorphic segment-specific programmed cell death, are the principal mechanisms of sculpting the sexually dimorphic abdomen of Drosophila.
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Chatterjee SS, Uppendahl LD, Chowdhury MA, Ip PL, Siegal ML. The female-specific doublesex isoform regulates pleiotropic transcription factors to pattern genital development in Drosophila. Development 2011; 138:1099-109. [PMID: 21343364 DOI: 10.1242/dev.055731] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Regulatory networks driving morphogenesis of animal genitalia must integrate sexual identity and positional information. Although the genetic hierarchy that controls somatic sexual identity in the fly Drosophila melanogaster is well understood, there are very few cases in which the mechanism by which it controls tissue-specific gene activity is known. In flies, the sex-determination hierarchy terminates in the doublesex (dsx) gene, which produces sex-specific transcription factors via alternative splicing of its transcripts. To identify sex-specifically expressed genes downstream of dsx that drive the sexually dimorphic development of the genitalia, we performed genome-wide transcriptional profiling of dissected genital imaginal discs of each sex at three time points during early morphogenesis. Using a stringent statistical threshold, we identified 23 genes that have sex-differential transcript levels at all three time points, of which 13 encode transcription factors, a significant enrichment. We focus here on three sex-specifically expressed transcription factors encoded by lozenge (lz), Drop (Dr) and AP-2. We show that, in female genital discs, Dsx activates lz and represses Dr and AP-2. We further show that the regulation of Dr by Dsx mediates the previously identified expression of the fibroblast growth factor Branchless in male genital discs. The phenotypes we observe upon loss of lz or Dr function in genital discs explain the presence or absence of particular structures in dsx mutant flies and thereby clarify previously puzzling observations. Our time course of expression data also lays the foundation for elucidating the regulatory networks downstream of the sex-specifically deployed transcription factors.
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Affiliation(s)
- Sujash S Chatterjee
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY 10003, USA
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Kuranaga E, Matsunuma T, Kanuka H, Takemoto K, Koto A, Kimura KI, Miura M. Apoptosis controls the speed of looping morphogenesis in Drosophila male terminalia. Development 2011; 138:1493-9. [PMID: 21389055 DOI: 10.1242/dev.058958] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In metazoan development, the precise mechanisms that regulate the completion of morphogenesis according to a developmental timetable remain elusive. The Drosophila male terminalia is an asymmetric looping organ; the internal genitalia (spermiduct) loops dextrally around the hindgut. Mutants for apoptotic signaling have an orientation defect of their male terminalia, indicating that apoptosis contributes to the looping morphogenesis. However, the physiological roles of apoptosis in the looping morphogenesis of male terminalia have been unclear. Here, we show the role of apoptosis in the organogenesis of male terminalia using time-lapse imaging. In normal flies, genitalia rotation accelerated as development proceeded, and completed a full 360° rotation. This acceleration was impaired when the activity of caspases or JNK or PVF/PVR signaling was reduced. Acceleration was induced by two distinct subcompartments of the A8 segment that formed a ring shape and surrounded the male genitalia: the inner ring rotated with the genitalia and the outer ring rotated later, functioning as a 'moving walkway' to accelerate the inner ring rotation. A quantitative analysis combining the use of a FRET-based indicator for caspase activation with single-cell tracking showed that the timing and degree of apoptosis correlated with the movement of the outer ring, and upregulation of the apoptotic signal increased the speed of genital rotation. Therefore, apoptosis coordinates the outer ring movement that drives the acceleration of genitalia rotation, thereby enabling the complete morphogenesis of male genitalia within a limited developmental time frame.
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Affiliation(s)
- Erina Kuranaga
- Department of Genetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, Japan.
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Suzanne M, Petzoldt AG, Spéder P, Coutelis JB, Steller H, Noselli S. Coupling of apoptosis and L/R patterning controls stepwise organ looping. Curr Biol 2010; 20:1773-8. [PMID: 20832313 DOI: 10.1016/j.cub.2010.08.056] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 08/25/2010] [Accepted: 08/25/2010] [Indexed: 10/19/2022]
Abstract
Handed asymmetry in organ shape and positioning is a common feature among bilateria, yet little is known about the morphogenetic mechanisms underlying left-right (LR) organogenesis. We utilize the directional 360° clockwise rotation of genitalia in Drosophila to study LR-dependent organ looping. Using time-lapse imaging, we show that rotation of genitalia by 360° results from an additive process involving two ring-shaped domains, each undergoing 180° rotation. Our results show that the direction of rotation for each ring is autonomous and strictly depends on the LR determinant myosin ID (MyoID). Specific inactivation of MyoID in one domain causes rings to rotate in opposite directions and thereby cancels out the overall movement. We further reveal a specific pattern of apoptosis at the ring boundaries and show that local cell death is required for the movement of each domain, acting as a brake-releaser. These data indicate that organ looping can proceed through an incremental mechanism coupling LR determination and apoptosis. Furthermore, they suggest a model for the stepwise evolution of genitalia posture in Diptera, through the emergence and duplication of a 180° LR module.
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Affiliation(s)
- Magali Suzanne
- University of Nice Sophia-Antipolis, CNRS, Institute of Developmental Biology and Cancer, Parc Valrose, 06108 Nice Cedex 2, France
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Rousset R, Bono-Lauriol S, Gettings M, Suzanne M, Spéder P, Noselli S. The Drosophila serine protease homologue Scarface regulates JNK signalling in a negative-feedback loop during epithelial morphogenesis. Development 2010; 137:2177-86. [PMID: 20530545 DOI: 10.1242/dev.050781] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
In Drosophila melanogaster, dorsal closure is a model of tissue morphogenesis leading to the dorsal migration and sealing of the embryonic ectoderm. The activation of the JNK signal transduction pathway, specifically in the leading edge cells, is essential to this process. In a genome-wide microarray screen, we identified new JNK target genes during dorsal closure. One of them is the gene scarface (scaf), which belongs to the large family of trypsin-like serine proteases. Some proteins of this family, like Scaf, bear an inactive catalytic site, representing a subgroup of serine protease homologues (SPH) whose functions are poorly understood. Here, we show that scaf is a general transcriptional target of the JNK pathway coding for a secreted SPH. scaf loss-of-function induces defects in JNK-controlled morphogenetic events such as embryonic dorsal closure and adult male terminalia rotation. Live imaging of the latter process reveals that, like for dorsal closure, JNK directs the dorsal fusion of two epithelial layers in the pupal genital disc. Genetic data show that scaf loss-of-function mimics JNK over-activity. Moreover, scaf ectopic expression aggravates the effect of the JNK negative regulator puc on male genitalia rotation. We finally demonstrate that scaf acts as an antagonist by negatively regulating JNK activity. Overall, our results identify the SPH-encoding gene scaf as a new transcriptional target of JNK signalling and reveal the first secreted regulator of the JNK pathway acting in a negative-feedback loop during epithelial morphogenesis.
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Affiliation(s)
- Raphaël Rousset
- University of Nice Sophia-Antipolis, UMR 6543 CNRS, Institute of Developmental Biology and Cancer, Parc Valrose, 06108 Nice CEDEX2, France
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Avanesian A, Semnani S, Jafari M. Can Drosophila melanogaster represent a model system for the detection of reproductive adverse drug reactions? Drug Discov Today 2009; 14:761-6. [PMID: 19482095 DOI: 10.1016/j.drudis.2009.05.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Revised: 04/30/2009] [Accepted: 05/13/2009] [Indexed: 01/25/2023]
Abstract
Once a molecule is identified as a potential drug, the detection of adverse drug reactions is one of the key components of its development and the FDA approval process. We propose using Drosophila melanogaster to screen for reproductive adverse drug reactions in the early stages of drug development. Compared with other non-mammalian models, D. melanogaster has many similarities to the mammalian reproductive system, including putative sex hormones and conserved proteins involved in genitourinary development. Furthermore, the D. melanogaster model would present significant advantages in time efficiency and cost-effectiveness compared with mammalian models. We present data on methotrexate (MTX) reproductive adverse events in multiple animal models, including fruit flies, as proof-of-concept for the use of the D. melanogaster model.
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Affiliation(s)
- Agnesa Avanesian
- Department of Pharmaceutical Sciences, University of California, Irvine, CA 92697, USA
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Mela A, Tsitilou SG, Yannopoulos G. Wiser (tsl): a recessive X-linked temperature-sensitive lethal mutation that affects the wings and the eyes in Drosophila melanogaster. Genetica 2008; 135:333-45. [PMID: 18536996 DOI: 10.1007/s10709-008-9281-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Accepted: 05/26/2008] [Indexed: 11/28/2022]
Abstract
In this study, we characterize a recessive X-linked temperature-sensitive mutation of the gene CG32711. The mutation, named wiser ( tsl ) (wings scalloped-eyes rough), was isolated from a dysgenic cross and is due to a natural P element insertion within the 5' regulatory region of the gene. Mutant (wiser ( tsl )) individuals exhibit wing notching, rough eyes, tarsal malformations and reduced life-span. At 29 degrees C they die at larval and late pharate stages or during eclosion. The CG32711 (wiser) gene is mainly expressed in the ventral midline cells, the peripheral neural system, the hemocytes and the tracheal system of embryos. It is also expressed in nurse cells of adult female ovaries. Our results show that the wiser gene is alternatively spliced generating two mRNAs, which share the same open reading frame, while western analysis identified two protein isoforms. Their expression pattern depends on the stage of development and the culture temperature. wiser ( tsl ) and wild-type individuals display different expression patterns of the two isoforms and this difference most probably accounts for the mutant phenotype. Our results indicate that wiser is a vital gene for the development of Drosophila melanogaster which has no orthologs outside the Drosophilidae.
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Affiliation(s)
- Angeliki Mela
- Division of Genetics, Cell and Developmental Biology, Department of Biology, University of Patras, University Campus, Rio, Patras, 26500, Greece
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42
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DeFalco T, Camara N, Le Bras S, Van Doren M. Nonautonomous sex determination controls sexually dimorphic development of the Drosophila gonad. Dev Cell 2008; 14:275-86. [PMID: 18267095 DOI: 10.1016/j.devcel.2007.12.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2007] [Revised: 10/18/2007] [Accepted: 12/11/2007] [Indexed: 11/30/2022]
Abstract
Sex determination in Drosophila is commonly thought to be a cell-autonomous process, where each cell decides its own sexual fate based on its sex chromosome constitution (XX versus XY). This is in contrast to sex determination in mammals, which largely acts nonautonomously through cell-cell signaling. Here we examine how sexual dimorphism is created in the Drosophila gonad by investigating the formation of the pigment cell precursors, a male-specific cell type in the embryonic gonad. Surprisingly, we find that sex determination in the pigment cell precursors, as well as the male-specific somatic gonadal precursors, is non-cell autonomous. Male-specific expression of Wnt2 within the somatic gonad triggers pigment cell precursor formation from surrounding cells. Our results indicate that nonautonomous sex determination is important for creating sexual dimorphism in the Drosophila gonad, similar to the manner in which sex-specific gonad formation is controlled in mammals.
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Affiliation(s)
- Tony DeFalco
- Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA
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43
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Chen SL, Dai SM, Lu KH, Chang C. Female-specific doublesex dsRNA interrupts yolk protein gene expression and reproductive ability in oriental fruit fly, Bactrocera dorsalis (Hendel). INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2008; 38:155-165. [PMID: 18207077 DOI: 10.1016/j.ibmb.2007.10.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2007] [Revised: 10/08/2007] [Accepted: 10/09/2007] [Indexed: 05/25/2023]
Abstract
A homologue of the doublesex gene (Bddsx) has been cloned from the oriental fruit fly, Bactrocera dorsalis (Hendel). Northern analysis indicates a differential expression of Bddsx in male and female flies, as reported for other dsx genes. A structural conservation of DNA binding domain/oligomerization domain 1 and oligomerization domain 2 suggests that the doublesex protein (BdDSX) of this fruit fly serves as a transcriptional factor for downstream sex-specific gene expression. The putative transformer/transformer-2 protein binding sequence in female-specific transcript suggests that a preserved alternative splicing process found in other flies mediates the synthesis of Bddsx transcript. RNA interference (RNAi) data from adult abdominal dsRNA injection assays indicate that female-specific dsx dsRNA reduces specifically its own transcript, inhibits selectively expression of the yolk protein gene (Bdyp1), and delays ovary development. The number of matured eggs is significant reduced after RNAi treatment, but the sex ratio of offspring is not biased. Moreover, 27% of female progeny with RNAi show deformed ovipositor, but male flies are not affected. Although this is a transient treatment, the specific Bddsx(f) interference offers a promising and novel approach to oriental fruit fly control in the future.
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Affiliation(s)
- Shiu-Ling Chen
- Department of Entomology, National Chung-Hsing University, Taichung 40227, Taiwan, ROC
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44
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Yang Y, Zhang W, Bayrer JR, Weiss MA. Doublesex and the regulation of sexual dimorphism in Drosophila melanogaster: structure, function, and mutagenesis of a female-specific domain. J Biol Chem 2008; 283:7280-92. [PMID: 18184648 DOI: 10.1074/jbc.m708742200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The DSX (Doublesex) transcription factor regulates somatic sexual differentiation in Drosophila. Female and male isoforms (DSX F and DSX M) are formed due to sex-specific RNA splicing. DNA recognition, mediated by a shared N-terminal zinc module (the DM domain), is enhanced by a C-terminal dimerization element. Sex-specific extension of this element in DSX F and DSX M leads to assembly of distinct transcriptional preinitiation complexes. Here, we describe the structure of the extended C-terminal dimerization domain of DSX F as determined by multidimensional NMR spectroscopy. The core dimerization element is well ordered, giving rise to a dense network of interresidue nuclear Overhauser enhancements. The structure contains dimer-related UBA folds similar to those defined by x-ray crystallographic studies of a truncated domain. Whereas the proximal portion of the female tail extends helix 3 of the UBA fold, the distal tail is disordered. Ala substitutions in the proximal tail disrupt the sex-specific binding of IX (Intersex), an obligatory partner protein and putative transcriptional coactivator; IX-DSX F interaction is, by contrast, not disrupted by truncation of the distal tail. Mutagenesis of the UBA-like dimer of DSX F highlights the importance of steric and electrostatic complementarity across the interface. Two temperature-sensitive mutations at this interface have been characterized in yeast model systems. One weakens a network of solvated salt bridges, whereas the other perturbs the underlying nonpolar interface. These mutations confer graded gene-regulatory activity in yeast within a physiological temperature range and so may provide novel probes for genetic analysis of a sex-specific transcriptional program in Drosophila development.
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Affiliation(s)
- Yanwu Yang
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106, USA
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45
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Wolff JR, Zarkower D. Chapter 1 Somatic Sexual Differentiation in Caenorhabditis elegans. Curr Top Dev Biol 2008; 83:1-39. [DOI: 10.1016/s0070-2153(08)00401-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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46
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Camara N, Whitworth C, Van Doren M. The creation of sexual dimorphism in the Drosophila soma. Curr Top Dev Biol 2008; 83:65-107. [PMID: 19118664 DOI: 10.1016/s0070-2153(08)00403-1] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Animals have evolved a fascinating array of mechanisms for conducting sexual reproduction. These include producing the sex-specific gametes, as well as mechanisms for attracting a mate, courting a mate, and getting the gametes together. These processes require that males and females take on dramatically different forms (sexual dimorphism). Here, we will explore the problem of how sex is determined in Drosophila, and pay particular attention to how information about sexual identity is used to instruct males and females to develop differently. Along the way, we will highlight new work that challenges some of the traditional views about sex determination. In Drosophila, it is commonly thought that every cell decides its own sex based on its sex chromosome constitution (XX vs. XY). However, we now know that many cell types undergo nonautonomous sex determination, where they are told what sex to be through signals from surrounding cells, independent of their own chromosomal content. Further, it now appears that not all cells even "know" their sex, since key members of the sex determination pathway are not expressed in all cells. Thus, our understanding of how sex is determined, and how sexual identity is used to create sexual dimorphism, has changed considerably.
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Affiliation(s)
- Nicole Camara
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA
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47
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Allen AK, Spradling AC. The Sf1-related nuclear hormone receptor Hr39 regulates Drosophila female reproductive tract development and function. Development 2007; 135:311-21. [PMID: 18077584 DOI: 10.1242/dev.015156] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The vertebrate nuclear hormone receptor steroidogenic factor 1 (SF1; NR5A1) controls reproductive development and regulates the transcription of steroid-modifying cytochrome P450 genes. We find that the SF1-related Drosophila nuclear hormone receptor HR39 is also essential for sexual development. In Hr39 mutant females, the sperm-storing spermathecae and glandular parovaria are absent or defective, causing sterility. Our results indicate that spermathecae and parovaria secrete reproductive tract proteins required for sperm maturation and function, like the mammalian epididymis and female reproductive tract. Hr39 controls the expression of specific cytochrome P450 genes and is required in females both to activate spermathecal secretion and repress male-specific courtship genes such as takeout. Thus, a pathway that, in vertebrates, controls sex-specific steroid hormone production, also mediates reproductive functions in an invertebrate. Our findings suggest that Drosophila can be used to model more aspects of mammalian reproductive biology than previously believed.
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Affiliation(s)
- Anna K Allen
- Howard Hughes Medical Institute, Department of Embryology, Carnegie Institution, 3520 San Martin Drive, Baltimore, MD 21218, USA
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48
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Hempel LU, Oliver B. Sex-specific DoublesexM expression in subsets of Drosophila somatic gonad cells. BMC DEVELOPMENTAL BIOLOGY 2007; 7:113. [PMID: 17935627 PMCID: PMC2148063 DOI: 10.1186/1471-213x-7-113] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Accepted: 10/12/2007] [Indexed: 12/02/2022]
Abstract
Background In Drosophila melanogaster, a pre-mRNA splicing hierarchy controls sexual identity and ultimately leads to sex-specific Doublesex (DSX) transcription factor isoforms. The male-specific DSXM represses genes involved in female development and activates genes involved in male development. Spatial and temporal control of dsx during embryogenesis is not well documented. Results Here we show that DSXM is specifically expressed in subsets of male somatic gonad cells during embryogenesis. Following testis formation, germ cells remain in contact with DSXM-expressing cells, including hub cells and premeiotic somatic cyst cells that surround germ cells during spermatogenesis in larval and adult testes. Conclusion We show that dsx is transcriptionally regulated in addition to being regulated at the pre-mRNA splicing level by the sex determination hierarchy. The dsx locus is spatially controlled by somatic gonad identity. The continuous expression of DSXM in cells contacting the germline suggests an ongoing short-range influence of the somatic sex determination pathway on germ cell development.
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Affiliation(s)
- Leonie U Hempel
- Laboratory of Cellular and Developmental Biology, NIDDK, National Institutes of Health, 50 South Drive, Bethesda MD 20892 USA.
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49
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Kamping A, Katju V, Beukeboom LW, Werren JH. Inheritance of gynandromorphism in the parasitic wasp Nasonia vitripennis. Genetics 2007; 175:1321-33. [PMID: 17179086 PMCID: PMC1840083 DOI: 10.1534/genetics.106.067082] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2006] [Accepted: 12/09/2006] [Indexed: 11/18/2022] Open
Abstract
The parasitic wasp Nasonia vitripennis has haplo-diploid sex determination. Males develop from unfertilized eggs and are haploid, whereas females develop from fertilized eggs and are diploid. Females and males can be easily distinguished by their morphology. A strain that produces individuals with both male and female features (gynandromorphs) is studied. We provide data on female/male patterning within and between individuals, on environmental effects influencing the occurrence of gynandromorphism, and on its pattern of inheritance. A clear anterior/posterior pattern of feminization is evident in gynandromorphic individuals that developed from unfertilized haploid eggs. The proportion of gynandromorphic individuals can be increased by exposing the mothers to high temperature and also by exposing embryos at early stages of development. Selection for increased gynandromorph frequency was successful. Backcross and introgression experiments showed that a combination of a nuclear and a heritable cytoplasmic component causes gynandromorphism. Analyses of reciprocal F(2) and F(3) progeny indicate a maternal effect locus (gyn1) that maps to chromosome IV. Coupled with previous studies, our results are consistent with a N. vitripennis sex determination involving a maternal/zygotic balance system and/or maternal imprinting. Genetics and temperature effects suggest a temperature-sensitive mutation of a maternally produced masculinizing product that acts during a critical period in early embryogenesis.
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Affiliation(s)
- Albert Kamping
- Evolutionary Genetics, Centre for Ecological and Evolutionary Studies, University of Groningen, NL-9750 AA Haren, The Netherlands
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50
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Chen EH, Christiansen AE, Baker BS. Allocation and specification of the genital disc precursor cells in Drosophila. Dev Biol 2006; 281:270-85. [PMID: 15893978 DOI: 10.1016/j.ydbio.2005.02.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2004] [Revised: 02/19/2005] [Accepted: 02/28/2005] [Indexed: 10/25/2022]
Abstract
The adult structures of Drosophila melanogaster are derived from larval imaginal discs, which originate as clusters of cells within the embryonic ectoderm. The genital imaginal disc is composed of three primordia (female genital, male genital, and anal primordia) that originate from the embryonic tail segments A8, A9, and A10, respectively, and produce the sexually dimorphic genitalia and analia. We show that the genital disc precursor cells (GDPCs) are first detectable during mid-embryogenesis as a 22-cell cluster in the ventral epidermis. Analysis of mutant and double mutant phenotypes of embryonic patterning genes in the GDPCs, together with their expression patterns in these cells, revealed the following with respect to the origins and specification of the GDPCs. The allocation of the GDPCs from the ventral epidermis requires the function of ventral patterning genes, including the EGF receptor and the spitz group of genes. The ventral localization of the GDPCs is further restricted by the action of dorsal patterning genes. Along the anterior-posterior axis, several segment polarity genes (wingless, engrailed, hedgehog, and patched) are required for the proper allocation of the GDPCs. These segment polarity genes are expressed in some, but not all of the GDPCs, indicating that anterior and posterior compartments are not fully established in the GDPCs. In addition, we found that the three primordia of the larval genital disc have already been specified in the GDPCs by the coordinated actions of the homeotic (Hox) genes, abdominal-A, Abdominal-B, and caudal. By identifying how these different patterning networks regulate the allocation and primordial organization of the 22 embryonic precursors of the compound genital disc, we demonstrate that at least some of the organization of the larval disc originates as positional information in the embryo, thus providing a context for further studies on the development of the genital disc.
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Affiliation(s)
- Elizabeth H Chen
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA
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