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The Role of CDKs and CDKIs in Murine Development. Int J Mol Sci 2020; 21:ijms21155343. [PMID: 32731332 PMCID: PMC7432401 DOI: 10.3390/ijms21155343] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 07/22/2020] [Accepted: 07/26/2020] [Indexed: 02/07/2023] Open
Abstract
Cyclin-dependent kinases (CDKs) and their inhibitors (CDKIs) play pivotal roles in the regulation of the cell cycle. As a result of these functions, it may be extrapolated that they are essential for appropriate embryonic development. The twenty known mouse CDKs and eight CDKIs have been studied to varying degrees in the developing mouse, but only a handful of CDKs and a single CDKI have been shown to be absolutely required for murine embryonic development. What has become apparent, as more studies have shone light on these family members, is that in addition to their primary functional role in regulating the cell cycle, many of these genes are also controlling specific cell fates by directing differentiation in various tissues. Here we review the extensive mouse models that have been generated to study the functions of CDKs and CDKIs, and discuss their varying roles in murine embryonic development, with a particular focus on the brain, pancreas and fertility.
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Palmer N, Talib SZA, Kaldis P. Diverse roles for CDK-associated activity during spermatogenesis. FEBS Lett 2019; 593:2925-2949. [PMID: 31566717 PMCID: PMC6900092 DOI: 10.1002/1873-3468.13627] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 09/20/2019] [Accepted: 09/26/2019] [Indexed: 12/22/2022]
Abstract
The primary function of cyclin-dependent kinases (CDKs) in complex with their activating cyclin partners is to promote mitotic division in somatic cells. This canonical cell cycle-associated activity is also crucial for fertility as it allows the proliferation and differentiation of stem cells within the reproductive organs to generate meiotically competent cells. Intriguingly, several CDKs exhibit meiosis-specific functions and are essential for the completion of the two reductional meiotic divisions required to generate haploid gametes. These meiosis-specific functions are mediated by both known CDK/cyclin complexes and meiosis-specific CDK-regulators and are important for a variety of processes during meiotic prophase. The majority of meiotic defects observed upon deletion of these proteins occur during the extended prophase I of the first meiotic division. Importantly a lack of redundancy is seen within the meiotic arrest phenotypes described for many of these proteins, suggesting intricate layers of cell cycle control are required for normal meiotic progression. Using the process of male germ cell development (spermatogenesis) as a reference, this review seeks to highlight the diverse roles of selected CDKs their activators, and their regulators during gametogenesis.
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Affiliation(s)
- Nathan Palmer
- Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore, Singapore.,Department of Biochemistry, National University of Singapore (NUS), Singapore, Singapore
| | - S Zakiah A Talib
- Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
| | - Philipp Kaldis
- Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Singapore, Singapore.,Department of Biochemistry, National University of Singapore (NUS), Singapore, Singapore.,Department of Clinical Sciences, Clinical Research Centre (CRC), Lund University, Malmö, Sweden
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Phosphoregulation of the oncogenic protein regulator of cytokinesis 1 (PRC1) by the atypical CDK16/CCNY complex. Exp Mol Med 2019; 51:1-17. [PMID: 30992425 PMCID: PMC6467995 DOI: 10.1038/s12276-019-0242-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 12/11/2018] [Accepted: 01/02/2019] [Indexed: 01/03/2023] Open
Abstract
CDK16 (also known as PCTAIRE1 or PCTK1) is an atypical member of the cyclin-dependent kinase (CDK) family that forms an active complex with cyclin Y (CCNY). Although both proteins have been recently implicated in cancer pathogenesis, it is still unclear how the CDK16/CCNY complex exerts its biological activity. To understand the CDK16/CCNY network, we used complementary proteomic approaches to identify potential substrates of this complex. We identified several candidates implicating the CDK16/CCNY complex in cytoskeletal dynamics, and we focused on the microtubule-associated protein regulator of cytokinesis (PRC1), an essential protein for cell division that organizes antiparallel microtubules and whose deregulation may drive genomic instability in cancer. Using analog-sensitive (AS) CDK16 generated by CRISPR-Cas9 mutagenesis in 293T cells, we found that specific inhibition of CDK16 induces PRC1 dephosphorylation at Thr481 and delocalization to the nucleus during interphase. The observation that CDK16 inhibition and PRC1 downregulation exhibit epistatic effects on cell viability confirms that these proteins can act through a single pathway. In conclusion, we identified PRC1 as the first substrate of the CDK16/CCNY complex and demonstrated that the proliferative function of CDK16 is mediated by PRC1 phosphorylation. As CDK16 is emerging as a critical node in cancer, our study reveals novel potential therapeutic targets. Studying the activity of proteins that work together to control cell division is revealing several that might be suitable targets for new drugs to fight cancer. Researchers led by Josep Clotet and Mariana Ribeiro at the International University of Catalonia, Barcelona, Spain, investigated the activities of the complex formed between two proteins, CDK16 and CCNY. CDK16 is an enzyme that modifies other molecules by adding phosphate groups (PO4) to them. CCNY is a protein that controls the activity of CDK16 and other proteins. Previous research has suggested a role for the complex in the development of cancer, but the mechanism has been unclear. The researchers found that the CDK16/CCNY complex activates proteins that control the network of microtubules in cells known as the cytoskeleton. One of these proteins, PRC1, is essential for cell division.
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Identification of novel PCTAIRE-1/CDK16 substrates using a chemical genetic screen. Cell Signal 2019; 59:53-61. [PMID: 30880224 DOI: 10.1016/j.cellsig.2019.03.012] [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: 02/16/2019] [Revised: 03/10/2019] [Accepted: 03/11/2019] [Indexed: 11/20/2022]
Abstract
PCTAIRE-1 (also known as cyclin-dependent protein kinase (CDK) 16), is a Ser/Thr kinase that has been implicated in many cellular processes, including cell cycle, spermatogenesis, neurite outgrowth, and vesicle trafficking. Most recently, it has been proposed as a novel X-linked intellectual disability (XLID) gene, where loss-of-function mutations have been identified in human patients. The precise molecular mechanisms that regulate PCTAIRE-1 remained largely obscure, and only a few cellular targets/substrates have been proposed with no clear functional significance. We and others recently showed that cyclin Y binds and activates PCTAIRE-1 via phosphorylation and 14-3-3 binding. In order to understand the physiological role that PCTAIRE-1 plays in brain, we have performed a chemical genetic screen in vitro using an engineered PCTAIRE-1/cyclin Y complex and mouse brain extracts. Our screen has identified potential PCTAIRE-1 substrates (AP2-Associated Kinase 1 (AAK1), dynamin 1, and synaptojanin 1) in brain that have been shown to regulate crucial steps of receptor endocytosis, and are involved in control of neuronal synaptic transmission. Furthermore, mass spectrometry and protein sequence analyses have identified potential PCTAIRE-1 regulated phosphorylation sites on AAK1 and we validated their PCTAIRE-1 dependence in a cellular study and/or brain tissue lysates. Our results shed light onto the missing link between PCTAIRE-1 regulation and proposed physiological functions, and provide a basis upon which to further study PCTAIRE-1 function in vivo and its potential role in neuronal/brain disorders.
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Zhao WP, Wang HW, Liu J, Tan PP, Lin L, Zhou BH. JNK/STAT signalling pathway is involved in fluoride-induced follicular developmental dysplasia in female mice. CHEMOSPHERE 2018; 209:88-95. [PMID: 29913403 DOI: 10.1016/j.chemosphere.2018.06.086] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 06/10/2018] [Accepted: 06/11/2018] [Indexed: 06/08/2023]
Abstract
Excessive fluoride (F) intake decreases the development of potential oocytes by inducing oxidative stress and apoptosis in female mice in our previous study. This study aims to investigate the underlying mechanisms of F-induced follicular developmental dysplasia. Pathomorphological changes in the ovary tissues were observed under light and transmission electron microscopes. DNA damage and proliferation in granulosa cells were analysed by TUNEL staining and BrdU measurement. The protein expression of cell proliferation related regulatory factors including JNK, STAT3, STAT5, CDK2, CDK4, PCNA and Ki67 in the ovary tissues was measured by immunohistochemistry and Western blot analyses. Results indicated that the structure of granulosa cells in the ovary was seriously damaged by excessive F, evident by the swollen endoplasmic reticulum, mitochondria with vacuoles and nucleus shrinkage. F treatment also considerably enhanced the apoptosis and inhibited the proliferation of granulosa cells. The number of granulosa cells around the oocyte decreased after F treatment. The expression levels of STAT3, CDK2, CDK4 and Ki67 in the ovary tissues were up-regulated, and STAT5 and PCNA did not change significantly after F treatment, whereas JNK expression was down-regulated with increasing F dose. In summary, changes in the expression levels of JNK, STAT3, STAT5, CDK2, CDK4, PCNA and Ki67 in the JNK/STAT signalling pathway are involved in F-induced follicular dysplasia in the ovary.
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Affiliation(s)
- Wen-Peng Zhao
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471000, PR China
| | - Hong-Wei Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471000, PR China.
| | - Jing Liu
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471000, PR China
| | - Pan-Pan Tan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471000, PR China
| | - Lin Lin
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471000, PR China
| | - Bian-Hua Zhou
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471000, PR China.
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Novel biomarker ZCCHC13 revealed by integrating DNA methylation and mRNA expression data in non-obstructive azoospermia. Cell Death Discov 2018. [PMID: 29531833 PMCID: PMC5841273 DOI: 10.1038/s41420-018-0033-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The objective of this study was to identify genes regulated by methylation that were involved in spermatogenesis failure in non-obstructive azoospermia (NOA). Testis biopsies of patients with NOA and OA (with normal spermatogenesis) were evaluated by microarray analysis to examine DNA methylation and mRNA expression using our established integrative approach. Of the coordinately hypermethylated and down-regulated gene list, zinc-finger CCHC-type containing 13 (ZCCHC13) was present within the nuclei of germ cells of testicular tissues according immunohistochemistry, and there was decreased protein expression in men with NOA compared with OA controls. Mechanistic analyses indicated that ZCCHC13 increased c-MYC expression through the p-AKT and p-ERK pathways. To confirm the changes in ZCCHC13 expression in response to methylation, 5-aza-2′-deoxycitidine (5-Aza), a hypomethylating agent, was administered to mouse spermatogonia GC-1 cells. We demonstrated that 5-Aza enhanced protein and mRNA expression of ZCCHC13 epigenetically, which was accompanied by activation of p-AKT and p-ERK signaling. Our data, for the first time, demonstrate that ZCCHC13 is an important signaling molecule that positively regulates the AKT/MAPK/c-MYC pathway and that methylation aberrations of ZCCHC13 may cause defects in testis development in human disease, such as NOA.
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Wang Y, Qin X, Guo T, Liu P, Wu P, Liu Z. Up-regulation of CDK16 by multiple mechanisms in hepatocellular carcinoma promotes tumor progression. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2017; 36:97. [PMID: 28716136 PMCID: PMC5514535 DOI: 10.1186/s13046-017-0569-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 07/12/2017] [Indexed: 02/07/2023]
Abstract
Background Hepatocellular carcinoma (HCC) remains difficult to cure due to lack of effective treatment and the molecular mechanisms are complex and not completely understood. In this study, We investigated the role of CDK16 in tumor progression of HCC. Methods We interrogated the expression level of CDK16 by polymerase chain reaction and immunohistochemistry(IHC) and studied its clinical significance. The functional role of CDK16 on HCC was studied via gain and loss of function in vitro and in vivo. Luciferase reporter assay and Chromatin immunoprecipitation(ChIP) assay were performed to investigate the transcriptional and post-transcriptional mechanisms involved in the regulation of CDK16. Results CDK16 expression was significantly up-regulated in HCC and higher expression of CDK16 was positively correlated with aggressive clinicopathological phenotype and poorer survival rates. Functionally, knockdown of CDK16 suppressed proliferation in vitro and in vivo. Inactivation of CDK16 also induced apoptosis and cell cycle arrest. Most importantly, CDK16 promoted epithelial mesenchymal transition and tumor invasion by activating β-catenin signaling. In addition, We identified E2F1 as a positive transcriptional regulator of CDK16. Moreover, down regulation of miR-125b-5p enhanced CDK16 expression at post-transcriptional level. Conclusion We provided the first evidence that CDK16 is an bona fide oncogene in HCC, and multiple activating mechanisms at transcriptional and posttranscriptional levels together contributes to CDK16 up-regulation in HCC. Electronic supplementary material The online version of this article (doi:10.1186/s13046-017-0569-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yitao Wang
- Department of General Surgery, Research Center of Digestive Diseases, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Xian Qin
- Department of General Surgery, Research Center of Digestive Diseases, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Tao Guo
- Department of General Surgery, Research Center of Digestive Diseases, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Pengpeng Liu
- Department of General Surgery, Research Center of Digestive Diseases, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Ping Wu
- Department of General Surgery, Research Center of Digestive Diseases, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Zhisu Liu
- Department of General Surgery, Research Center of Digestive Diseases, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China.
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Agrimson KS, Onken J, Mitchell D, Topping TB, Chiarini-Garcia H, Hogarth CA, Griswold MD. Characterizing the Spermatogonial Response to Retinoic Acid During the Onset of Spermatogenesis and Following Synchronization in the Neonatal Mouse Testis. Biol Reprod 2016; 95:81. [PMID: 27488029 PMCID: PMC5176362 DOI: 10.1095/biolreprod.116.141770] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 07/25/2016] [Indexed: 11/06/2022] Open
Abstract
Retinoic acid (RA), the active metabolite of vitamin A, is known to be required for the differentiation of spermatogonia. The first round of spermatogenesis initiates in response to RA and occurs in patches along the length of the seminiferous tubule. However, very little is known about the individual differentiating spermatogonial populations and their progression through the cell cycle due to the heterogeneous nature of the onset of spermatogenesis. In this study, we utilized WIN 18,446 and RA as tools to generate testes enriched with different populations of spermatogonia to further investigate 1) the undifferentiated to differentiating spermatogonial transition, 2) the progression of the differentiating spermatogonia through the cell cycle, and 3) Sertoli cell number in response to altered RA levels. WIN 18,446/RA-treated neonatal mice were used to determine when synchronous S phases occurred in the differentiating spermatogonial population following treatment. Five differentiating spermatogonial S phase windows were identified between spermatogonial differentiation and formation of preleptotene spermatocytes. In addition, a slight increase in Sertoli cell number was observed following RA treatment, possibly implicating a role for RA in Sertoli cell cycle progression. This study has enhanced our understanding of the spermatogonial populations present in the neonatal testis during the onset of spermatogenesis by mapping the cell cycle kinetics of both the undifferentiated and the differentiating spermatogonial populations and identifying the precise timing of when specific individual differentiating spermatogonial populations are enriched within the testis following synchrony, thus providing an essential tool for further study of the differentiating spermatogonia.
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Affiliation(s)
- Kellie S Agrimson
- School of Molecular Biosciences and the Center for Reproductive Biology, Washington State University, Pullman, Washington
| | - Jennifer Onken
- School of Molecular Biosciences and the Center for Reproductive Biology, Washington State University, Pullman, Washington
| | - Debra Mitchell
- School of Molecular Biosciences and the Center for Reproductive Biology, Washington State University, Pullman, Washington
| | - Traci B Topping
- School of Molecular Biosciences and the Center for Reproductive Biology, Washington State University, Pullman, Washington
| | - Hélio Chiarini-Garcia
- Laboratory of Structural Biology and Reproduction, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Pampulha, Belo Horizonte, MG, Brazil
| | - Cathryn A Hogarth
- School of Molecular Biosciences and the Center for Reproductive Biology, Washington State University, Pullman, Washington
| | - Michael D Griswold
- School of Molecular Biosciences and the Center for Reproductive Biology, Washington State University, Pullman, Washington
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Shimizu K, Uematsu A, Imai Y, Sawasaki T. Pctaire1/Cdk16 promotes skeletal myogenesis by inducing myoblast migration and fusion. FEBS Lett 2014; 588:3030-7. [PMID: 24931367 DOI: 10.1016/j.febslet.2014.05.060] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 05/29/2014] [Accepted: 05/29/2014] [Indexed: 01/17/2023]
Abstract
The Cdk-related protein kinase Pctaire1/Cdk16 is abundantly expressed in brain, testis and skeletal muscle. Functional roles of Pctaire1 such as regulation of neuron migration and neurite outgrowth thus far have been mainly elucidated in the field of nervous system development. Although these regulations based on cytoskeletal rearrangements evoke a possible role of Pctaire1 in the development of skeletal muscle, little is known in this regard. In this study, we demonstrated that myogenic differentiation and subsequent fusion is promoted in Pctaire1 overexpressing cells, and conversely, is inhibited in the knockdown cells. Furthermore, our findings suggest that Pctaire1 exerts promyogenic effects by regulating myoblast migration and process formation during skeletal myogenesis.
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Affiliation(s)
- Kouhei Shimizu
- Division of Cell-Free Sciences, Proteo-Science Center, Ehime University, Matsuyama 790-8577, Japan
| | - Atsushi Uematsu
- Division of Cell-Free Sciences, Proteo-Science Center, Ehime University, Matsuyama 790-8577, Japan
| | - Yuuki Imai
- Division of Integrative Pathophysiology, Proteo-Science Center, Graduate School of Medicine, Ehime University, Toon 791-0295, Japan
| | - Tatsuya Sawasaki
- Division of Cell-Free Sciences, Proteo-Science Center, Ehime University, Matsuyama 790-8577, Japan; The Venture Business Laboratory, Ehime University, Matsuyama 790-8577, Japan.
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10
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Chen J, Liu P, Li Z, Chen Y, Qiu GF. The cloning of the cdk2 transcript and the localization of its expression during gametogenesis in the freshwater giant prawn, Macrobrachium rosenbergii. Mol Biol Rep 2013; 40:4781-90. [PMID: 23653005 DOI: 10.1007/s11033-013-2574-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 04/29/2013] [Indexed: 11/28/2022]
Abstract
Cyclin-dependent kinases (cdks) are key regulators of the cell cycle. In mammals, cdk2 plays an essential role in the meiosis of spermatocytes and oocytes. To investigate the role of cdk2 kinase during gametogenesis in crustaceans, we cloned a complete cDNA sequence of cdk2 from the freshwater giant prawn, Macrobrachium rosenbergii, and examined its localization and expression in the developing gonads. The prawn cdk2 cDNA is 1,745 bp in length and encodes a putative protein of 305 amino acids. The deduced protein contains a conserved cyclin binding motif PSTAIRE and shares high homology with reported cdk2 kinases of other species. RT-PCR analysis showed a wide distribution of the cdk2 mRNA in all tested organs including the testis, ovary, heart, muscles, hepatopancreas and gills, and the highest level of expression in the ovary and testis. Localization by in situ hybridization of cdk2 mRNA in the ovary showed high expression in the ooplasm of previtellogenic and the nuclei of late vitellogenic oocytes. In testicular sections, cdk2 transcript is low in spermatogonia, high in spermatocytes, but reduced in spermatids and sperm. The high expression of the cdk2 transcripts in meiotic spermatocytes and oocytes indicated that the cdk2 gene has the conservative function in the germ cells meiosis during gametogenesis.
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Affiliation(s)
- Jie Chen
- Key Laboratory of Aquatic Genetic Resources and Utilization Certificated by the Ministry of Agriculture, College of Life Science, Shanghai Ocean University, 999 Hucheng Huan Road, Pudong New Area, Shanghai, 201306, People's Republic of China
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Mikolcevic P, Rainer J, Geley S. Orphan kinases turn eccentric: a new class of cyclin Y-activated, membrane-targeted CDKs. Cell Cycle 2012; 11:3758-68. [PMID: 22895054 DOI: 10.4161/cc.21592] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
PCTAIRE kinases (PCTK) are a highly conserved, but poorly characterized, subgroup of cyclin-dependent kinases (CDK). They are characterized by a conserved catalytic domain flanked by N- and C-terminal extensions that are involved in cyclin binding. Vertebrate genomes contain three highly similar PCTAIRE kinases (PCTK1,2,3, a.k.a., CDK16,17,18), which are most abundant in post-mitotic cells in brain and testis. Consistent with this restricted expression pattern, PCTK1 (CDK16) has recently been shown to be essential for spermatogenesis. PCTAIREs are activated by cyclin Y (CCNY), a highly conserved single cyclin fold protein. By binding to N-myristoylated CCNY, CDK16 is targeted to the plasma membrane. Unlike conventional cyclin-CDK interactions, binding of CCNY to CDK16 not only requires the catalytic domain, but also domains within the N-terminal extension. Interestingly, phosphorylation within this domain blocks CCNY binding, providing a novel means of cyclin-CDK regulation. By using these functional characteristics, we analyzed "PCTAIRE" sequence containing protein kinase genes in genomes of various organisms and found that CCNY and CCNY-dependent kinases are restricted to eumetazoa and possibly evolved along with development of a central nervous system. Here, we focus on the structure and regulation of PCTAIREs and discuss their established functions.
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Affiliation(s)
- Petra Mikolcevic
- Division of Molecular Pathophysiology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
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12
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Shehata SN, Hunter RW, Ohta E, Peggie MW, Lou HJ, Sicheri F, Zeqiraj E, Turk BE, Sakamoto K. Analysis of substrate specificity and cyclin Y binding of PCTAIRE-1 kinase. Cell Signal 2012; 24:2085-94. [PMID: 22796189 PMCID: PMC3590450 DOI: 10.1016/j.cellsig.2012.06.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 06/25/2012] [Indexed: 12/29/2022]
Abstract
PCTAIRE-1 (cyclin-dependent kinase [CDK] 16) is a highly conserved serine/threonine kinase that belongs to the CDK family of protein kinases. Little is known regarding PCTAIRE-1 regulation and function and no robust assay exists to assess PCTAIRE-1 activity mainly due to a lack of information regarding its preferred consensus motif and the lack of bona fide substrates. We used positional scanning peptide library technology and identified the substrate-specificity requirements of PCTAIRE-1 and subsequently elaborated a peptide substrate termed PCTAIRE-tide. Recombinant PCTAIRE-1 displayed vastly improved enzyme kinetics on PCTAIRE-tide compared to a widely used generic CDK substrate peptide. PCTAIRE-tide also greatly improved detection of endogenous PCTAIRE-1 activity. Similar to other CDKs, PCTAIRE-1 requires a proline residue immediately C-terminal to the phosphoacceptor site (+ 1) for optimal activity. PCTAIRE-1 has a unique preference for a basic residue at + 4, but not at + 3 position (a key characteristic for CDKs). We also demonstrate that PCTAIRE-1 binds to a novel cyclin family member, cyclin Y, which increased PCTAIRE-1 activity towards PCTAIRE-tide > 100-fold. We hypothesised that cyclin Y binds and activates PCTAIRE-1 in a way similar to which cyclin A2 binds and activates CDK2. Point mutants of cyclin Y predicted to disrupt PCTAIRE-1-cyclin Y binding severely prevented complex formation and activation of PCTAIRE-1. We have identified PCTAIRE-tide as a powerful tool to study the regulation of PCTAIRE-1. Our understanding of the molecular interaction between PCTAIRE-1 and cyclin Y further facilitates future investigation of the functions of PCTAIRE-1 kinase.
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Affiliation(s)
- Saifeldin N Shehata
- MRC Protein Phosphorylation Unit, College of Life Sciences, University of Dundee, Dundee, UK
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Gopinathan L, Ratnacaram CK, Kaldis P. Established and novel Cdk/cyclin complexes regulating the cell cycle and development. Results Probl Cell Differ 2011; 53:365-89. [PMID: 21630153 DOI: 10.1007/978-3-642-19065-0_16] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The identification of new members in the Cdk and cyclin families, functions for many of which are still emerging, has added new facets to the cell cycle regulatory network. With roles extending beyond the classical regulation of cell cycle progression, these new players are involved in diverse processes such as transcription, neuronal function, and ion transport. Members closely related to Cdks and cyclins such as the Speedy/RINGO proteins offer fresh insights and hope for filling in the missing gaps in our understanding of cell division. This chapter will present a broad outlook on the cell cycle and its key regulators with special emphasis on the less-studied members and their emerging roles.
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Affiliation(s)
- Lakshmi Gopinathan
- Cell Division and Cancer Laboratory (PRK), Institute of Molecular and Cell Biology (IMCB), 61 Biopolis Drive, Proteos #03-09, Singapore
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14
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Qiu GF, Ramachandra RK, Rexroad CE, Yao J. Molecular characterization and expression profiles of cyclin B1, B2 and Cdc2 kinase during oogenesis and spermatogenesis in rainbow trout (Oncorhynchus mykiss). Anim Reprod Sci 2008; 105:209-25. [PMID: 17399922 DOI: 10.1016/j.anireprosci.2007.03.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Accepted: 03/01/2007] [Indexed: 11/17/2022]
Abstract
The meiotic maturation of oocyte and spermatocyte in animals is controlled by the maturation promotion factor (MPF), a complex of Cdc2 and cyclin B proteins. To better understand the mechanism of oocyte and spermatocyte maturation in fish, the expression of cyclin B1 (CB1), B2 (CB2) and Cdc2 kinase during oogenesis and spermatogenesis in rainbow trout were examined at both the mRNA and protein levels. Quantitative real-time PCR analysis showed that the amount of CB1 and CB2 mRNA was greater at previtellogenesis and late vitellogenesis stages, but less at early vitellogenesis stage and during early embryogenesis. Cdc2 mRNA was continuously present throughout the processes of oogenesis and early embryogenesis except for a decline at early vitellogenesis. In situ hybridization analysis indicated that CB1, CB2 and Cdc2 transcripts were present in oocytes of different developmental stages as well as in all spermatogenic cells except for spermatogonia. Immunohistochemical analysis revealed that CB1 protein was absent in vitellogenic oocytes, but present in young previtellogenic and mature oocytes. In contrast, CB2 and Cdc2 proteins were present at all stages oocyte development. Similarly, CB2 and Cdc2 proteins were present throughout spermatogenesis, whereas CB1 protein was only detected in spermatogonia and spermatocytes, but not in spermatids. Thus, it appears that CB1, CB2 and Cdc2 transcripts have similar expression patterns during oogenesis and spermatogenesis, but CB1 protein varies in amount during these processes. These data suggest that CB1 may have a leading role in the regulation of meiotic maturation of oocytes and spermotocytes.
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Affiliation(s)
- Gao-Feng Qiu
- Division of Animal and Veterinary Sciences, West Virginia University, Morgantown, WV 26506-6108, USA
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Buchold GM, Magyar PL, Arumugam R, Lee MM, O'Brien DA. p19Ink4d and p18Ink4c cyclin-dependent kinase inhibitors in the male reproductive axis. Mol Reprod Dev 2007; 74:997-1007. [PMID: 17342741 DOI: 10.1002/mrd.20716] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The loss of the cyclin-dependent kinase inhibitors (CKIs) p18(Ink4c) and p19(Ink4d) leads to male reproductive defects (Franklin et al., 1998. Genes Dev 12: 2899-2911; Zindy et al., 2000. Mol Cell Biol 20: 372-378; Zindy et al., 2001. Mol Cell Biol 21: 3244-3255). In order to assess whether these inhibitors directly or indirectly affect male germ cell differentiation, we examined the expression of p18(Ink4c) and p19(Ink4d) in spermatogenic and supporting cells in the testis and in pituitary gonadotropes. Both p18(Ink4c) and p19(Ink4d) are most abundant in the testis after 18 days of age and are expressed in purified populations of spermatogenic and testicular somatic cells. Different p18(Ink4c) mRNAs are expressed in isolated spermatogenic and Leydig cells. Spermatogenic cells also express a novel p19(Ink4d) transcript that is distinct from the smaller transcript expressed in Sertoli cells, Leydig cells and in other tissues. Immunohistochemistry detected significant levels of p19(Ink4d) in preleptotene spermatocytes, pachytene spermatocytes, condensing spermatids, and Sertoli cells. Immunoprecipitation-Western analysis detected both CKI proteins in isolated pachytene spermatocytes and round spermatids. CDK4/6-CKI complexes were detected in germ cells by co-immunoprecipitation, although the composition differed by cell type. p19(Ink4d) was also identified in FSH+ gonadotrophs, suggesting that this CKI may be independently required in the pituitary. Possible cell autonomous and paracrine mechanisms for the spermatogenic defects in mice lacking p18(Ink4c) or p19(Ink4d) are supported by expression of these CKIs in spermatogenic cells and in somatic cells of the testis and pituitary.
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Affiliation(s)
- Gregory M Buchold
- Curriculum in Genetics and Molecular Biology, The University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
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16
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Abstract
In yeast, a single cyclin-dependent kinase (Cdk) is able to regulate diverse cell cycle transitions (S and M phases) by associating with multiple stage-specific cyclins. The evolution of multicellular organisms brought additional layers of cell cycle regulation in the form of numerous Cdks, cyclins and Cdk inhibitors to reflect the higher levels of organismal complexity. Our current knowledge about the mammalian cell cycle emerged from early experiments using human and rodent cell lines, from which we built the current textbook model of cell cycle regulation. In this model, the functions of different cyclin/Cdk complexes were thought to be specific for each cell cycle phase. In the last decade, studies using genetically engineered mice in which cell cycle regulators were targeted revealed many surprises. We discovered the in vivo functions of cell cycle proteins within the context of a living animal and whether they are essential for animal development. In this review, we discuss first the textbook model of cell cycle regulation, followed by a global overview of data obtained from different mouse models. We describe the similarities and differences between the phenotypes of different mouse models including embryonic lethality, sterility, hematopoietic, pancreatic, and placental defects. We also describe the role of key cell cycle regulators in the development of tumors in mice, and the implications of these data for human cancer. Furthermore, animal models in which two or more genes are ablated revealed which cell cycle regulators interact genetically and functionally complement each other. We discuss for example the interaction of cyclin D1 and p27 and the compensation of Cdk2 by Cdc2. We also focus on new functions discovered for certain cell cycle regulators such as the regulation of S phase by Cdc2 and the role of p27 in regulating cell migration. Finally, we conclude the chapter by discussing the limitations of animal models and to what extent can the recent findings be reconciled with the past work to come up with a new model for cell cycle regulation with high levels of redundancy among the molecular players.
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Affiliation(s)
- Eiman Aleem
- National Cancer Institute, Mouse Cancer Genetics Program, NCI-Frederick, MD 21702-1201, USA
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17
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Liu Y, Cheng K, Gong K, Fu AKY, Ip NY. Pctaire1 phosphorylates N-ethylmaleimide-sensitive fusion protein: implications in the regulation of its hexamerization and exocytosis. J Biol Chem 2006; 281:9852-8. [PMID: 16461345 DOI: 10.1074/jbc.m513496200] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Pctaire1, a member of the cyclin-dependent kinase (Cdk)-related family, has recently been shown to be phosphorylated and regulated by Cdk5/p35. Although Pctaire1 is expressed in both neuronal and non-neuronal cells, its precise functions remain elusive. We performed a yeast two-hybrid screen to identify proteins that interact with Pctaire1. N-Ethylmaleimide-sensitive fusion protein (NSF), a crucial factor in vesicular transport and membrane fusion, was identified as one of the Pctaire1 interacting proteins. We demonstrate that the D2 domain of NSF, which is required for the oligomerization of NSF subunits, binds directly to and is phosphorylated by Pctaire1 on serine 569. Mutation of this phosphorylation site on NSF (S569A) augments its ability to oligomerize. Moreover, inhibition of Pctaire1 activity by transfecting its kinase-dead (KD) mutant into COS-7 cells enhances the self-association of NSF. Interestingly, Pctaire1 associates with NSF and synaptic vesicle-associated proteins in adult rat brain. To investigate whether Pctaire1 phosphorylation of NSF is involved in regulation of Ca(2+)-dependent exocytosis, we examined the effect of expressing Pctaire1 or NSF phosphorylation mutants on the regulated secretion of growth hormone from PC12 cells. Interestingly, expression of either Pctaire1-KD or NSF-S569A in PC12 cells significantly increases high K(+)-stimulated growth hormone release. Taken together, our findings provide the first demonstration that Pctaire1 phosphorylation of NSF regulates the ability of NSF to oligomerize, implicating an unexpected role of this kinase in modulating exocytosis. These findings open a new avenue of research in studying the functional roles of Pctaire1 in the nervous system.
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Affiliation(s)
- Yuxin Liu
- Department of Biochemistry, Biotechnology Research Institute, and Molecular Neuroscience Center, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
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18
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Lin YM, Teng YN, Chung CL, Tsai WC, Lin YH, Lin JSN, Kuo PL. Decreased mRNA transcripts of M-phase promoting factor and its regulators in the testes of infertile men. Hum Reprod 2005; 21:138-44. [PMID: 16155078 DOI: 10.1093/humrep/dei285] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND M-phase promoting factor (MPF), which is comprised of Cyclin B and a catalytic subunit, Cdc2, is a key enzyme required for cells to enter M phase in both mitosis and meiosis. MPF activity is controlled by the stimulatory dephosphorylation of the Cdc25 family and the inhibitory phosphorylation of Wee1. We determined the levels of mRNA transcripts of MPF and its regulators in the testes of infertile men, and evaluated the relationship between the transcript levels and patients' testicular phenotypes and sperm retrieval results. METHODS AND RESULTS The mRNA transcript levels of CDC2, CCNB1, CCNB2, CDC25A, CDC25B, CDC25C and WEE1 in the testes of 37 azoospermic patients were examined by quantitative real-time polymerase chain reaction. Significant decreases in CDC2, CCNB1, CCNB2, CDC25A, CDC25C and WEE1 mRNA transcript levels were detected in patients with spermatogenic failure. CDC2 mRNA transcript levels correlated significantly with those of CCNB1 and CCNB2 mRNA. Significantly higher CDC2, CCNB1, CCNB2, CDC25C and WEE1 mRNA transcript levels were detected in 18 patients with successful sperm retrieval than in 11 patients with failed sperm retrieval. CONCLUSIONS We suggest that the decreased mRNA transcripts of MPF and its regulators play important roles in human spermatogenesis.
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Affiliation(s)
- Yung Ming Lin
- Department of Urology, National Cheng Kung University, College of Medicine, Tainan, Taiwan
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19
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Herskovits AZ, Davies P. Generation and Characterization of Monoclonal Antibodies to Human PCTAIRE 3. Hybridoma (Larchmt) 2005; 24:98-105. [PMID: 15857174 DOI: 10.1089/hyb.2005.24.98] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Monoclonal antibodies specific for the unique N-terminal domain of the PCTAIRE 3 protein kinase have been produced and characterized. The specificity of these antibodies has been assessed by ELISA, Western blot, and immunoflorescence techniques. These reagents are specific for recombinant PCTAIRE 3 of human origin and do not cross-react with PCTAIRE 1 or PCTAIRE 2, despite the high homology between members of the PCTAIRE subfamily of cdc2-like kinases. Immunoblotting of transfected cells reveals that all of the antibodies recognize both isoforms of the PCTAIRE 3 kinase. Epitope mapping reveals three distinct classes of PCTAIRE 3 antibodies that recognize different sites within an immunodominant region of the N-terminal domain of the protein. The creation of highly specific PCTAIRE 3 monoclonal reagents will be useful for assessing the native distribution and function of this protein.
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Affiliation(s)
- A Z Herskovits
- Albert Einstein College of Medicine of Yeshiva University, Bronx, New York 10461, USA.
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20
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Herskovits AZ, Davies P. Cloning and expression analysis of two novel PCTAIRE 3 transcripts from human brain. Gene 2004; 328:59-67. [PMID: 15019984 DOI: 10.1016/j.gene.2003.12.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2003] [Revised: 12/02/2003] [Accepted: 12/12/2003] [Indexed: 10/26/2022]
Abstract
PCTAIRE 3 is a member of the PCTAIRE subfamily of cdc2-related serine/threonine protein kinases. In the present study, cDNAs encoding two isoforms of PCTAIRE 3 have been cloned and the genomic organization of the human PCTAIRE 3 gene is reported. The gene spans 28.15 kb on chromosome 1q31-32 and contains 16 exons. The major transcript of PCTAIRE 3, designated PCTAIRE 3a, has an open reading frame that is 474 amino acids in length. Transcripts for PCTAIRE 3a were evident throughout the brain and in the majority of tissues analyzed. A second transcript containing an insert that adds 90 nucleotides to the third exon of the gene was also identified. This transcript, designated PCTAIRE 3b, encodes a polypeptide of 504 amino acids. Expression of PCTAIRE 3b was limited to several subcortical nuclei of the basal gangli and the spinal cord and substantial levels of this transcript were not evident outside of the central nervous system. Primary sequence comparisons between different cdc2-related serine/threonine protein kinases reveal that these proteins are most heterogeneous in their N-terminal domains and the PCTAIRE subfamily is further diversified by the presence of isoforms within this region.
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Affiliation(s)
- A Z Herskovits
- Albert Einstein College of Medicine, Departments of Neuroscience and Pathology, F526, 1300 Morris Park Ave, Bronx, NY 10461, USA
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21
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Trousdale RK, Wolgemuth DJ. Bromodomain containing 2 (Brd2) is expressed in distinct patterns during ovarian folliculogenesis independent of FSH or GDF9 action. Mol Reprod Dev 2004; 68:261-8. [PMID: 15112318 DOI: 10.1002/mrd.20059] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We previously observed high levels of Brd2 (also known as female sterile homeotic related gene-1, Fsrg1) expression in several hormonally responsive tissues, including the ovary. Here, we report distinct localization patterns of Brd2 transcripts throughout ovarian folliculogenesis in normal mice as well as in two strains of mice with aberrant folliculogenesis: mice with mutated growth differentiation factor 9 (Gdf9) and follicle stimulating hormone beta (Fshb) genes. The highest level of expression was seen in granulosa cells of growing follicles. Within the oocyte, three patterns of Brd2 RNA localization were observed: diffuse distribution in both the cytoplasm and nucleus, then intense nuclear expression, followed by an absence of Brd2 transcripts from the nucleus. The transition from intense nuclear localization to nuclear exclusion was found to correlate with oocyte maturation and meiotic competence, as determined by nuclear chromatin patterns. These same expression patterns were also seen in oocytes from Gdf9(-/-) and Fshb(-/-) mice. Thus, Brd2 expression appears to correlate with stages of oocyte maturation, independent of FSH or GDF9 action and the subsequent disruption in normal follicle development in these models. The distinct patterns of Brd2 localization within the adult ovary supports a role for Brd2 in mitotic and possibly meiotic cell cycle regulation.
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Affiliation(s)
- Rhonda K Trousdale
- Departments of Genetics and Development and Obstetrics and Gynecology, The Center for Reproductive Sciences, The Institute of Human Nutrition, Columbia University Medical Center, New York, New York 10032, USA
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22
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Crowley T, Brunori M, Rhee K, Wang X, Wolgemuth DJ. Change in nuclear-cytoplasmic localization of a double-bromodomain protein during proliferation and differentiation of mouse spinal cord and dorsal root ganglia. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2004; 149:93-101. [PMID: 15063089 DOI: 10.1016/j.devbrainres.2003.12.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/31/2003] [Indexed: 11/19/2022]
Abstract
The human Brd2 (Bromodomain-containing 2) gene codes for a double-bromodomain protein that associates with the cell cycle-driving transcription factors E2F-1 and E2F-2. Expression of mouse Brd2 has been shown previously to be expressed in specific patterns in proliferating cells in the developing alveoli in the mammary gland. In the present study, in situ hybridization and immunohistochemical analyses were used to examine expression of Brd2 in developing neural tissues. Brd2 mRNA was detected in brain vesicles, neural tube, spinal cord and dorsal root ganglia (DRG). Immunostaining proved that the message is translated in these tissues and further revealed that Brd2 protein localizes to the nucleus in proliferating cells, but is cytoplasmic in differentiated neurons that are no longer cycling. Brd2 protein in the nuclei of the proliferating neuronal precursors is excluded from the heterochromatin. These observations are consistent with our previous finding that nuclear localization of Brd2 protein correlates with an active cell cycle in mouse mammary alveoli during the reproductive cycle, and similar results from others in cultured fibroblasts. Our findings are also consistent with the cell cycle progression/transcription coactivator function suggested by the association of Brd2 with E2F-1 and E2F-2.
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Affiliation(s)
- ThomasE Crowley
- Department of Obstetrics and Gynecology, Columbia University Medical Center, 630 W 168th St., New York, NY 10032, USA
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23
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Liao C, Li SQ, Wang X, Muhlrad S, Bjartell A, Wolgemuth DJ. Elevated levels and distinct patterns of expression of A-type cyclins and their associated cyclin-dependent kinases in male germ cell tumors. Int J Cancer 2004; 108:654-64. [PMID: 14696091 DOI: 10.1002/ijc.11573] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Aberrant expression of several key regulators controlling the G1/S phase of the cell cycle has been implicated in human male germ cell tumorigenesis. Given the critical role of cyclin A2 at both the G1/S and G2/M transitions and the essential role for cyclin A1 in male germ cell development, our present study focused on the involvement of the A-type cyclins in the transformation and progression of male germ cell tumors (GCTs). The expression of the A-type cyclins and their catalytic partners Cdk1 and Cdk2 was examined in all types and stages of human male GCTs, including carcinoma in situ(CIS), seminoma and non-seminoma GCTs, along with normal testis samples. Elevated levels of cyclin A2, Cdk1 and Cdk2 were detected in the majority of GCTs and were correlated with the invasiveness of the tumors (p < 0.05). Cyclin A1 expression was virtually undetectable in CIS and seminoma, but was aberrantly expressed in all non-seminomatous GCTs. Cyclin A2 expression was strongly correlated with that of its catalytic partners Cdk1 and Cdk2 in all types of testicular tumors examined (p < 0.05), whereas a strong correlation between cyclin A1 and Cdk1 or Cdk2 was only seen in non-seminomatous GCTs (p < 0.05). Histone kinase activities of cyclin A1/Cdks and cyclin A2/Cdks were found to be elevated in tumors. Our data suggest that aberrant expression of A-type cyclins and their Cdks is a significant factor in male germ cell tumorigenesis. The abundant ectopic expression of cyclin A1 in non-seminomatous GCTs and its absence in CIS and seminomas is likely linked to the tumor transformation and progression and may be relevant to clinical prognosis.
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Affiliation(s)
- Ching Liao
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, NY, USA
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24
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Wilson HL, O'Neill HC. Identification of differentially expressed genes representing dendritic cell precursors and their progeny. Blood 2003; 102:1661-9. [PMID: 12750154 DOI: 10.1182/blood-2002-08-2426] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The development of dendritic cells (DCs) from hematopoietic progenitors is not well understood. Using a spleen-derived long-term culture (LTC) system, it has been possible to continuously generate DCs from progenitors maintained in culture. The nonadherent LTC-DC population is composed of 2 major subsets. These are the small LTC-DC or DC precursors and their progeny, the large LTC-DCs that phenotypically resemble immature DCs. In this study, subtracted cDNA libraries were generated containing sequences differentially expressed in small or large LTC-DCs. Differential screening was then used on plated library clones to select genes expressed in either the small or the large cell population. Real-time polymerase chain reaction (PCR) has been used to verify the selection procedure for several genes of particular interest. Known genes isolated from subtracted libraries were related to stages in DC development and supported previous findings regarding the function of small and large LTC-DCs. Large LTC-DCs expressed a number of immunologically important genes encoding CD86, CCR1, osteopontin, and lysozyme. Small LTC-DCs resembled progenitor DCs expressing genes related to the organization of the cytoskeleton, the regulation of antigen processing, and a number of mitochondrial and ribosomal proteins. Novel transcripts were isolated from small and large LTC-DC-subtracted libraries that could encode novel proteins important in DC development. This study describes changes in gene expression related to the development of CD11c+CD11b+ major histocompatibility complex 2 low (MHC2lo) CD8alpha- DCs from precursors in a stroma-dependent culture system in the absence of exogenous cytokines.
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Affiliation(s)
- Heather L Wilson
- School of Biochemistry and Molecular Biology, Faculty of Science, The Australian National University, Canberra, ACT, 0200, Australia
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25
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Graeser R, Gannon J, Poon RYC, Dubois T, Aitken A, Hunt T. Regulation of the CDK-related protein kinase PCTAIRE-1 and its possible role in neurite outgrowth in Neuro-2A cells. J Cell Sci 2002; 115:3479-90. [PMID: 12154078 DOI: 10.1242/jcs.115.17.3479] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PCTAIRE-1 is a CDK-related protein kinase found in terminally differentiated cells in brain and testis, and in many immortalised and transformed cell lines. Bacterially expressed PCTAIRE is completely inactive as a protein kinase, but is a very good substrate for protein kinase A (PKA),which phosphorylates a total of four sites in the N-terminus of PCTAIRE-1. Phosphorylation of one of these sites, Ser119, generates a 14-3-3 binding site, which is functional in vitro as well as in vivo. Mutation of another PKA site, Ser153, to an alanine residue generated an activated kinase in transfected mammalian cells. This activity was comparable to that of CDK5 activated by a bacterially expressed, truncated version of p35nck,p21. Gel filtration analysis of a brain extract suggested that monomeric PCTAIRE-1 was the active species, implying that PCTAIRE-1 may not be a true CDK, in that it does not require a partner (cyclin-like) subunit for kinase activity. Finally, we found that various forms of PCTAIRE-1 transfected into neuroblastoma cell lines could either promote or inhibit neurite outgrowth,suggesting a potential role for the PCTAIRE-1 gene product in the control of neurite outgrowth.
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Affiliation(s)
- Ralph Graeser
- ICRF Clare Hall Laboratories, South Mimms, Herts EN6 3LD, UK.
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26
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Crowley TE, Kaine EM, Yoshida M, Nandi A, Wolgemuth DJ. Reproductive cycle regulation of nuclear import, euchromatic localization, and association with components of Pol II mediator of a mammalian double-bromodomain protein. Mol Endocrinol 2002; 16:1727-37. [PMID: 12145330 DOI: 10.1210/me.2001-0353] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Fsrg1 (female sterile homeotic-related gene 1) is the mouse homolog of the human RING3 protein, which has been shown to associate with the E2 promoter binding factor (E2F) transcription factor and to have a possible role in cell cycle-linked transcriptional regulation. The Fsrg1 protein is 60% identical in sequence to the RNA polymerase II mediator subunit Fsrg4, another member of this subfamily of double bromodomain-containing proteins that are homologs of Drosophila female sterile homeotic. Antibodies against murine Fsrg1 were generated and used in immunoblot and immunoprecipitation experiments to identify proteins interacting with Fsrg1 and RING3. In the presence of acetylated but not nonacetylated histone H3 and H4 peptides, RING3 was shown to interact with E2F, mediator components cyclin-dependent kinase 8 and thyroid receptor-associated protein 220, and the RNA polymerase II large subunit. Fsrg1 mRNA had been previously shown to be expressed at high levels in the epithelium of the adult mouse mammary gland. To determine the physiological relevance of these potential associations, we examined the patterns of expression of Fsrg1 mRNA and protein in the adult mammary epithelia during the reproductive cycle as the tissue is responding to estrogen, progesterone, and prolactin. Changes in the nuclear vs. cytoplasmic localization of Fsrg1 were observed and correlated with physiological changes in mammary gland function. The observations suggested that Fsrg1 may be involved in the transcriptional activities of genes involved in proliferation of the mammary epithelia during pregnancy and in orchestrating postlactation involution and apoptosis. Localization of Fsrg1 on euchromatin, the transcribed portion of the chromosomes, is consistent with its hypothesized function as a transcription regulator.
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Affiliation(s)
- Thomas E Crowley
- Department of Obstetrics and Gynecology, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA
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Wishart MJ, Dixon JE. The archetype STYX/dead-phosphatase complexes with a spermatid mRNA-binding protein and is essential for normal sperm production. Proc Natl Acad Sci U S A 2002; 99:2112-7. [PMID: 11842224 PMCID: PMC122327 DOI: 10.1073/pnas.251686198] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Differentiation of spermatids into spermatozoa is regulated via phosphorylated RNA-binding proteins that modulate the expression of stage-specific mRNAs. We demonstrate that the phosphoserine, -threonine or -tyrosine, interaction protein, Styx, complexes with a testicular RNA-binding protein and is essential for normal spermiogenesis. Ablation of Styx expression in mouse disrupts round and elongating spermatid development, resulting in a >1,000-fold decrease in spermatozoa production. Moreover, Styx(-/-) males are infertile because of structural head abnormalities in residual epididymal sperm. Immunoprecipitation of Styx with Crhsp-24, a phosphorylated RNA-binding protein implicated in translational repression of histone mRNAs, provides a strategy for regulating posttranscriptional gene expression.
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Affiliation(s)
- Matthew J Wishart
- Life Sciences Institute and Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
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28
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Cipriano SC, Chen L, Burns KH, Koff A, Matzuk MM. Inhibin and p27 interact to regulate gonadal tumorigenesis. Mol Endocrinol 2001; 15:985-96. [PMID: 11376116 DOI: 10.1210/mend.15.6.0650] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Tumor suppressors function as antiproliferative signaling proteins, and defects in these genes lead to uncontrolled cell proliferation and cancer. For example, absence of the tumor suppressor p27(Kip1), a cyclin-dependent kinase inhibitor (CKI), results in increased body size, hyperplasia of several organs including the testes, and cancer in mice. Similarly, lack of inhibins, alpha/beta heterodimeric members of the transforming growth factor-beta (TGFbeta) superfamily, causes testicular and ovarian tumors of the granulosa/Sertoli cell lineage beginning at 4 weeks of age and adrenal tumors in gonadectomized mice. Neither the cell cycle alterations in the absence of inhibin nor the cause of the increased testis size in the p27 knockout mice is known. To study the molecular (cell cycle) changes that result from absence of inhibins, we analyzed the regulation of cell cycle proteins in gonadal tumors derived from inhibin alpha knockout mice (Inha(-/-)). Northern blot analyses demonstrate that cyclin-dependent kinase 4 (Cdk4) and cyclin D2 mRNA levels are elevated, and immunohistochemistry shows that p27 protein levels are decreased in both ovarian and testicular tumors from Inha(-/-) mice. These findings suggest that increased Cdk4/cyclin D2 (positive) activity and decreased p27 (negative) activity is causal for gonadal tumor formation. To test this hypothesis, we generated double mutant mice lacking both p27 and inhibin alpha to determine whether the tumor suppressors p27 and inhibin have additive suppressor activity in the gonads. Like Inha(-/-) mice, p27(-/-)Inha(-/-) mice demonstrate elevated serum activin levels, ovarian and testicular tumors, and a resultant lethal cachexia-like syndrome. However, whereas 95% of the Inha(-/-) female mice die by 18 weeks of age, 100% of the p27(-/-)Inha(-/-) female mice are dead by 8 weeks. Similarly, 95% of the Inha(-/-) single mutant males die by 13 weeks while 100% of the p27(-/-)Inha(-/-) male mice die by 10 weeks. Moreover, tumor foci in p27(-/-)Inha(-/-) mice can be observed as early as 2 weeks of age in males and as early as 4 weeks in females. These findings demonstrate that absence of both inhibin and p27 in mice causes earlier development of ovarian and testicular tumors and earlier death compared with absence of inhibin alone.
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Affiliation(s)
- S C Cipriano
- Department of Pathology, Baylor College of Medicine,One Baylor Plaza, Houston, TX 77030, USA
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Ohuchi J, Arai T, Kon Y, Asano A, Yamauchi H, Watanabe T. Characterization of a novel gene, sperm-tail-associated protein (Stap), in mouse post-meiotic testicular germ cells. Mol Reprod Dev 2001; 59:350-8. [PMID: 11468771 DOI: 10.1002/mrd.1041] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
During mammalian spermatogenesis, many specific molecules show the dynamics of expression and elimination, corresponding with the morphological differentiation of germ cells. We have isolated a novel cDNA designated F77 from mouse testis by cDNA subtractive hybridization between normal and sterile mice, using the C57BL/6 congenic strain for the hybrid sterilityhyphen;3 lpar;Hsthyphen;3rpar; allele from Mus spretus. The full-length F77 mRNA was 3.4 kb and showed significant nonmatching with entries in the databases. F77 was mapped at a proximal position between D8Mit212 and D8Mit138 on mouse chromosome 8, in which no corresponding genes related to its nucleotide sequence were found. F77 mRNA was not detected in any other organs except the testis of adult fertile mice. F77 protein was only seen in normal adult testis and epididymis. In contrast to normal C57BL/6 mice, F77 mRNA and protein were not seen in germ cell-deficient Kit(W)/Kit(Wv) mice. By in situ hybridization, F77 mRNA was detected mainly at round spermatids in the sexually mature testis, and immunohistochemical analysis revealed that F77 protein was located at the tail of elongated spermatids. We are proposing the name, sperm-tail-associated protein (Stap), for the gene encoding F77 cDNA. Mol. Reprod. Dev. 59: 350-358, 2001.
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Affiliation(s)
- J Ohuchi
- Laboratory of Experimental Animal Science, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
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30
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Zindy F, den Besten W, Chen B, Rehg JE, Latres E, Barbacid M, Pollard JW, Sherr CJ, Cohen PE, Roussel MF. Control of spermatogenesis in mice by the cyclin D-dependent kinase inhibitors p18(Ink4c) and p19(Ink4d). Mol Cell Biol 2001; 21:3244-55. [PMID: 11287627 PMCID: PMC86968 DOI: 10.1128/mcb.21.9.3244-3255.2001] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2000] [Accepted: 02/13/2001] [Indexed: 12/31/2022] Open
Abstract
Male mice lacking both the Ink4c and Ink4d genes, which encode two inhibitors of D-type cyclin-dependent kinases (Cdks), are infertile, whereas female fecundity is unaffected. Both p18(Ink4c) and p19(Ink4d) are expressed in the seminiferous tubules of postnatal wild-type mice, being largely confined to postmitotic spermatocytes undergoing meiosis. Their combined loss is associated with the delayed exit of spermatogonia from the mitotic cell cycle, leading to the retarded appearance of meiotic cells that do not properly differentiate and instead undergo apoptosis at an increased frequency. As a result, mice lacking both Ink4c and Ink4d produce few mature sperm, and the residual spermatozoa have reduced motility and decreased viability. Whether or not Ink4d is present, animals lacking Ink4c develop hyperplasia of interstitial testicular Leydig cells, which produce reduced levels of testosterone. The anterior pituitary of fertile mice lacking Ink4c or infertile mice doubly deficient for Ink4c and Ink4d produces normal levels of luteinizing hormone (LH). Therefore, the failure of Leydig cells to produce testosterone is not secondary to defects in LH production, and reduced testosterone levels do not account for infertility in the doubly deficient strain. By contrast, Ink4d-null or double-null mice produce elevated levels of follicle-stimulating hormone (FSH). Because Ink4d-null mice are fertile, increased FSH production by the anterior pituitary is also unlikely to contribute to the sterility observed in Ink4c/Ink4d double-null males. Our data indicate that p18(Ink4c) and p19(Ink4d) are essential for male fertility. These two Cdk inhibitors collaborate in regulating spermatogenesis, helping to ensure mitotic exit and the normal meiotic maturation of spermatocytes.
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Affiliation(s)
- F Zindy
- Departments of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
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31
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Ashley T, Walpita D, de Rooij DG. Localization of two mammalian cyclin dependent kinases during mammalian meiosis. J Cell Sci 2001; 114:685-93. [PMID: 11171374 DOI: 10.1242/jcs.114.4.685] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Mammalian meiotic progression, like mitotic cell cycle progression, is regulated by cyclins and cyclin dependent kinases (CDKs). However, the unique requirements of meiosis (homologous synapsis, reciprocal recombination and the dual divisions that segregate first homologues, then sister chromatids) have led to different patterns of CDK expression. Here we show that Cdk4 colocalizes with replication protein A (RPA) on the synaptonemal complexes (SCs) of newly synapsed axes of homologously pairing bivalents, but disappears from these axes by mid-pachynema. The switch from the mitotic pattern of expression occurs during the last two spermatogonial divisions. Cdk2 colocalizes with MLH1, a mismatch repair protein at sites of reciprocal recombination in mid-late pachynema. In addition Cdk2 localizes to the telomeres of chromosomal bivalents throughout meiotic prophase. The mitotic pattern of expression of Cdk2 remains unchanged throughout the spermatogonial divisions, but is altered in meiosis of the spermatocytes.
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Affiliation(s)
- T Ashley
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06510, USA
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32
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Kong WH, Zheng G, LU JN, Tso JK. Temperature dependent expression of cdc2 and cyclin B1 in spermatogenic cells during spermatogenesis. Cell Res 2000; 10:289-302. [PMID: 11191351 DOI: 10.1038/sj.cr.7290056] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
p34cdc2 and Cyclin B1 are key components of cell cycle controlling machine and are believed to play a fundamental role in gametogenesis. It is also well known that, in scrotal mammals, spermatogenesis depends greatly on the maintenance of comparatively low temperature in the scrotum. To investigate whether the expression of cdc2 and cyclin B1 in spermatogenic cells during spermatogenesis is actually a temperature dependent event, in situ hybridization, Western blotting and immunohistochemistry analysis were used to study the expression of cdc2 and cyclin B1 in normal and cryptorchid testis. Results showed that the abdominal temperature had no significant influence on the transcription of cdc2 and cyclin B1 in the spermatogonia and pachytene/diplotene primary spermatocytes, but it blocked the translation of them. Due to the deficiency of p34cdc2 and Cyclin B1, the spermatogonia and pachytene/diplotene primary spermatocytes were unable to form MPF, hence, they couldn't undergo karyokinesis. The development of primary spermatocytes was arrested at the G2 to M phase transition. We also found that testosterone could regulate the Cyclin B1 expression in spermatogenic cells. Muscular injection of testosterone could recover spermatogenesis in the unilateral scrotal testis which was influenced by the contralateral cryptorchid testis, but it could not salvage the spermatogenesis block in the cryptorchid testis.
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Affiliation(s)
- W H Kong
- Shanghai Institute of Planned Parenthood Research, China
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33
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Godet M, Thomas A, Rudkin BB, Durand P. Developmental changes in cyclin B1 and cyclin-dependent kinase 1 (CDK1) levels in the different populations of spermatogenic cells of the post-natal rat testis. Eur J Cell Biol 2000; 79:816-23. [PMID: 11139145 DOI: 10.1078/0171-9335-00107] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Spermatogenesis is a highly ordered process which requires mitotic and meiotic divisions. In this work, we studied the relative changes in the levels of the two components of the M-phase promoting factor (MPF): the regulatory subunit cyclin B1 (CycB1) and its catalytic subunit cdk1, in spermatogenic cells of rats between 16 and 90 days of life. A multivariate flow cytometry analysis of forward scatter (FSC), side scatter (SSC) and DNA content was used to identify six populations of rat germ cells: spermatogonia with preleptotene spermatocytes, young pachytene spermatocytes, middle to late pachytene spermatocytes, secondary spermatocytes with doublets of round spermatids, round spermatids, and elongated spermatids. For any population studied no significant difference in the relative cellular content of CycB1 or cdk1 proteins between animals of different ages was observed. By contrast, CycB1 and cdk1 levels were different between the different populations of germ cells. CycB1 and cdk1 were rather high in young pachytene spermatocytes and culminated in late spermatocytes, i.e. just before the first meiotic division. The relative levels of the two proteins remained high in secondary spermatocytes then decreased in round spermatids at the exit of meiosis. Similar results were obtained by Western-blot analysis of total proteins obtained from lysates of elutriated fractions of spermatocytes and spermatids. MPF activity was assessed in lysates of germ cells from 32-day-old rats or adult animals using p13suc1 agarose and histone H1 as an exogenous substrate. H1 kinase activity was higher in pachytene spermatocytes than in round spermatid fractions from both adult and young rats. These results indicate that the meiotic G2/M transition is associated to high levels of CycB1 and cdk1 leading to high MPF activity irrespective of the age of the animals.
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Affiliation(s)
- M Godet
- INSERM-INRA U 418, H pital Debrousse, Lyon, France
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34
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Le Bouffant F, Le Minter P, Traiffort E, Ruat M, Sladeczek F. Multiple subcellular localizations of PCTAIRE-1 in brain. Mol Cell Neurosci 2000; 16:388-95. [PMID: 11085876 DOI: 10.1006/mcne.2000.0881] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We developed a selective antibody to a synthetic peptide corresponding to an N-terminal sequence of the PCTAIRE-1 protein. In rodent brain extracts it recognized only the protein doublet characteristic of PCTAIRE-1, and this signal is completely abolished by preincubation of the antibody with the immunopeptide. Immunolabeling experiments done with this PCTAIRE-1-specific antibody reveal that the protein is widely distributed in the rodent brain as are the mRNAs visualized using an antisense riboprobe corresponding to the entire PCTAIRE-1 open reading frame. Two types of PCTAIRE-1 protein localizations were observed: first a diffuse labeling of almost all brain regions, particularly intense in the molecular layer of the cerebellum and the mossy fiber region of the hippocampus, and second a spot-like localization in the nuclei of large neurons such as cerebellar Purkinje cells and pyramidal cells of the hippocampus. Colocalization with the B23 protein allows one to identify these compartments as nucleoli. Our results suggest a nucleolar function of PCTAIRE-1 in large neurons and a role in regions containing important granule cell projections.
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Affiliation(s)
- F Le Bouffant
- CNRS UPR 2212, Institut Alfred Fessard, Gif-sur-Yvette, France
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35
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Xue JC, Goldberg E. Identification of a novel testis-specific leucine-rich protein in humans and mice. Biol Reprod 2000; 62:1278-84. [PMID: 10775177 DOI: 10.1095/biolreprod62.5.1278] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
A novel testis-specific protein, termed LRTP, was identified by screening both human and mouse testis and mouse pachytene spermatocyte cDNA libraries. Sequence analyses (GenBank accession number: AF092208) revealed that LRTP contains an amino terminus leucine-rich repeat domain. There are several acidic regions rich in glutamic acid in the C-terminus. The sequence, by GenBank search, shows similarities to LANP and SDS22+, leucine-rich repeat proteins localized to the nucleus and involved in the regulation of protein phosphatases. In mouse, the mRNA is first detected at about Day 14 postpartum, presumably when mid-pachytene spermatocytes are first seen. In situ hybridization confirmed the expression of the LRTP mRNA at this stage of spermatogenesis. Immunohistochemical analysis revealed that the protein is most abundant in the cytoplasm of pachytene and diplotene cells, corresponding to late prophase of meiosis I. Immunohistochemical localization is markedly reduced in secondary spermatocytes, suggesting a functional association of LRTP with meiosis. An LRTP cDNA probe did not bind to mouse ovary RNA in a dot blot assay.
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Affiliation(s)
- J C Xue
- Department of Biochemistry, Molecular Biology & Cell Biology, Northwestern University, Evanston, Illinois 60208, USA
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36
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Hirose T, Kawabuchi M, Tamaru T, Okumura N, Nagai K, Okada M. Identification of tudor repeat associator with PCTAIRE 2 (Trap). A novel protein that interacts with the N-terminal domain of PCTAIRE 2 in rat brain. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:2113-21. [PMID: 10727952 DOI: 10.1046/j.1432-1327.2000.01218.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PCTAIRE 2 is a Cdc2-related kinase that is predominantly expressed in the terminally differentiated neuron. To elucidate the function of PCTAIRE 2, proteins that associate with PCTAIRE 2 were screened by the yeast two-hybrid system. A positive clone was found to encode a novel protein that could bind to PCTAIRE 2 in vitro as well as in vivo, and was designated as Trap (tudor repeat associator with PCTAIRE 2). The overall structure of Trap shows no significant homology to any proteins, but contains five repeated domains (the tudor-like domain), conserved in Drosophila tudor protein. Trap associates with the N-terminal domain of PCTAIRE 2 through its C-terminal domain, which contains two tudor-like domains. PCTAIRE 1, but not PCTAIRE 3, can also associate with Trap. Trap is predominantly expressed in brain and testis, and gradually increases during brain development throughout life, consistent with the expression pattern of PCTAIRE 2. Immunoreactivities for PCTAIRE 2 and Trap were colocalized to the mitochondria in COS 7 cells. Immunohistochemical analyses showed that PCTAIRE 2 and Trap were distributed in the same cell layer of the cerebral cortex and cerebellum. These findings suggest that Trap is a physiological partner of PCTAIRE 2 in terminally differentiated neurons.
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Affiliation(s)
- T Hirose
- Division of Protein Metabolism, Institute for Protein Research, Osaka University, Japan.
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37
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Zindy F, van Deursen J, Grosveld G, Sherr CJ, Roussel MF. INK4d-deficient mice are fertile despite testicular atrophy. Mol Cell Biol 2000; 20:372-8. [PMID: 10594039 PMCID: PMC85092 DOI: 10.1128/mcb.20.1.372-378.2000] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/1999] [Accepted: 09/22/1999] [Indexed: 12/19/2022] Open
Abstract
The INK4 family of cyclin-dependent kinase (CDK) inhibitors includes four 15- to 19-kDa polypeptides (p16(INK4a), p15(INK4b), p18(INK4c), and p19(INK4d)) that bind to CDK4 and CDK6. By disrupting cyclin D-dependent holoenzymes, INK4 proteins prevent phosphorylation of the retinoblastoma protein and block entry into the DNA-synthetic phase of the cell division cycle. The founding family member, p16(INK4a), is a potent tumor suppressor in humans, whereas involvement, if any, of other INK4 proteins in tumor surveillance is less well documented. INK4c and INK4d are expressed during mouse embryogenesis in stereotypic tissue-specific patterns and are also detected, together with INK4b, in tissues of young mice. INK4a is expressed neither before birth nor at readily appreciable levels in young animals, but its increased expression later in life suggests that it plays some checkpoint function in response to cell stress, genotoxic damage, or aging per se. We used targeted gene disruption to generate mice lacking INK4d. These animals developed into adulthood, had a normal life span, and did not spontaneously develop tumors. Tumors did not arise at increased frequency in animals neonatally exposed to ionizing radiation or the carcinogen dimethylbenzanthrene. Mouse embryo fibroblasts, bone marrow-derived macrophages, and lymphoid T and B cells isolated from these animals proliferated normally and displayed typical lineage-specific differentiation markers. Males exhibited marked testicular atrophy associated with increased apoptosis of germ cells, although they remained fertile. The absence of tumors in INK4d-deficient animals demonstrates that, unlike INK4a, INK4d is not a tumor suppressor but is instead involved in spermatogenesis.
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Affiliation(s)
- F Zindy
- Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
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38
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Steiner R, Ever L, Don J. MEIG1 localizes to the nucleus and binds to meiotic chromosomes of spermatocytes as they initiate meiosis. Dev Biol 1999; 216:635-45. [PMID: 10642798 DOI: 10.1006/dbio.1999.9520] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Meiosis, the fundamental evolutionarily conserved differentiative process by which haploid gametes are produced, is a complex and tightly regulated nuclear process. The murine Meig1 gene was previously shown to have a germ cell-specific transcript which is abundantly expressed during meiosis, in both males and females, suggesting that it is involved in meiotic processes. Protein analysis revealed that MEIG1 appears in multiple phosphorylated forms, including two dimeric forms of M(r) 31,000 and 32,000, which exhibit a developmentally regulated switch in their relative abundance. The tyrosine-phosphorylated M(r) 31,000 form becomes the dominant form once the cells enter meiosis. In this study we show that the M(r) 31,000 dimeric form appears in the nuclear fraction of testicular protein extract, whereas the M(r) 32,000 dimeric form and the monomeric forms of MEIG1 remain cytoplasmic. The appearance in the nuclear fraction is developmentally regulated, coinciding with progression of the first spermatogenic wave through meiotic prophase I. Utilizing immunocytochemistry we show that nuclear localization is apparent in primary spermatocytes through their maturation into elongated spermatozoa, but not in either somatic cells or germ cells from early postnatal pups. We also show that MEIG1 associates specifically with meiotic chromosomes in vivo. These results indicate that in germ cells, the M(r) 31,000 dimeric form enters the nucleus during the first meiotic prophase and binds to the meiotic chromatin. Possible nuclear functions, as well as possible modes of nuclear localization, are discussed.
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Affiliation(s)
- R Steiner
- Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
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39
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Kon Y, Endoh D, Iwanaga T. Expression of protein gene product 9.5, a neuronal ubiquitin C-terminal hydrolase, and its developing change in sertoli cells of mouse testis. Mol Reprod Dev 1999; 54:333-41. [PMID: 10542373 DOI: 10.1002/(sici)1098-2795(199912)54:4<333::aid-mrd3>3.0.co;2-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Protein gene product 9.5 (PGP9.5), originally isolated as a neuron-specific protein, belongs to a family of ubiquitin carboxyl-terminal hydrolases that play important roles in the nonlysosomal proteolytic pathway. Antibodies against PGP9.5 have been used for immunohistochemical detection of neural elements, although some non-neuronal cells are also immunoreactive for PGP9.5. In the present study, developing testes of the mouse were immunostained after autoclave pretreatment of sections. In the testes of days 8 and 16, PGP9.5 was only localized on the spermatogonia, whereas on day 30 and in adults it appeared not only on spermatogonia, but also on Sertoli cells. In the testis of the male sterile W/W(v) mutant, very little, but strong, immunoreactivity was detected at some Sertoli cells, which were phagocytizing Sertoli cell aggregations that had fallen from the basal membrane. Additionally, it was confirmed that the nucleotide sequence of PGP9.5 in mice was highly conserved, like that in other mammals. These results suggest that PGP9.5 is a useful marker for activated Sertoli cells, playing an important role in degradation of abnormal proteins.
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Affiliation(s)
- Y Kon
- Laboratory of Experimental Animal Science, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
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40
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Allemand I, Anglo A, Jeantet AY, Cerutti I, May E. Testicular wild-type p53 expression in transgenic mice induces spermiogenesis alterations ranging from differentiation defects to apoptosis. Oncogene 1999; 18:6521-30. [PMID: 10597255 DOI: 10.1038/sj.onc.1203052] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
While p53 is dispensable for development, an excess of p53 has dramatic consequences on the embryogenesis and on the cell differentiation. In an attempt to analyse in vivo the effects of p53 activity, we have generated transgenic mice expressing the wild-type p53 under the control of the metallothionein I promoter. In the three transgenic lines established, exogenous p53 is expressed constitutively in the postmeiotic cells of transgenic males and two lines are subfertile. Transgenic males expressing the upper level of p53 produce few spermatozoa since the majority of developing spermatids undergo apoptosis. In the subfertile males exhibiting an intermediate amount of p53, teratozoospermia is obvious suggesting an altered terminal differentiation of postmeiotic cells. In contrast lower level of p53 does not lead the third line to sterility. These results suggest that the activity of p53 is dependent in vivo on the amount of p53 present within cells, as it has been already demonstrated in vitro.
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Affiliation(s)
- I Allemand
- UMR 217 CNRS-CEA, Laboratoire de Cancérogenèse Moléculaire, DRR- DSV- CEA, Fontenay-aux-Roses, France
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41
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McDonald JP, Rapić-Otrin V, Epstein JA, Broughton BC, Wang X, Lehmann AR, Wolgemuth DJ, Woodgate R. Novel human and mouse homologs of Saccharomyces cerevisiae DNA polymerase eta. Genomics 1999; 60:20-30. [PMID: 10458907 DOI: 10.1006/geno.1999.5906] [Citation(s) in RCA: 159] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Saccharomyces cerevisiae RAD30 gene encodes a novel eukaryotic DNA polymerase, pol eta that is able to replicate across cis-syn cyclobutane pyrimidine dimers both accurately and efficiently. Very recently, a human homolog of RAD30 was identified, mutations in which result in the sunlight-sensitive, cancer-prone, Xeroderma pigmentosum variant group phenotype. We report here the cloning and localization of a second human homolog of RAD30. Interestingly, RAD30B is localized on chromosome 18q21.1 in a region that is often implicated in the etiology of many human cancers. The mouse homolog (Rad30b) is located on chromosome 18E2. The human RAD30B and mouse Rad30b mRNA transcripts, like many repair proteins, are highly expressed in the testis. In situ hybridization analysis indicates that expression of mouse Rad30b occurs predominantly in postmeiotic round spermatids. Database searches revealed genomic and EST sequences from other eukaryotes such as Aspergillus nidulans, Schizosaccharomyces pombe, Brugia malayi, Caenorhabditis elegans, Trypanosoma cruzi, Arabidopsis thaliana, and Drosophila melanogaster that also encode putative homologs of RAD30, thereby suggesting that Rad30-dependent translesion DNA synthesis is conserved within the eukaryotic kingdom.
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Affiliation(s)
- J P McDonald
- Section on DNA Replication, Repair and Mutagenesis, National Institute of Child Health and Human Development, Bethesda, Maryland, 20892-2725, USA
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42
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Détivaud L, Pettit GR, Meijer L. Characterization of a novel cdk1-related kinase. EUROPEAN JOURNAL OF BIOCHEMISTRY 1999; 264:55-66. [PMID: 10447673 DOI: 10.1046/j.1432-1327.1999.00576.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The p13suc1/p9CKShs proteins bind tightly to the cyclin-dependent kinases cdk1 and cdk2. The distantly related protein, p15cdk-BP, binds cdk4/6, cdk5 and cdk8. We now show that immobilized p15cdk-BP binds both an HMG-I kinase and a 35-kDa protein that cross-reacts with anti-PSTAIRE antibodies (PSTAIRE is a totally conserved motif located in subdomain III of cdk). This 'cdkX' and the HMG-I kinase also bind to an immobilized inhibitor of cdks (HD). Several properties clearly distinguish cdkX, and its associated HMG-I kinase, from known anti-PSTAIRE cross-reactive cdks: (a) cdkX migrates, in SDS/PAGE, in a position intermediate between prophase phosphorylated cdk1 and metaphase dephosphorylated cdk1; (b) in contrast with cdk1, cdkX and associated HMG-I kinase activity do not decrease following successive depletions on p9CKShs1-sepharose; (c) cdkX and associated HMG-I kinase activity, but not cdk1, decrease following depletions on immobilized inhibitor; (d) cdkX is expressed during the early development of sea urchin embryos; in contrast with cdk1/cyclin B kinase, the p15cdk-BP-bound HMG-I kinase is active throughout the cell cycle; compared with cdk1 it is active later in development; (e) p15cdk-BP-bound HMG-I kinase is essentially insensitive to powerful inhibitors of cdk such as purvalanol, roscovitine, olomoucine, p21cip1 and p16INK4A; HD is only moderately inhibitory. Altogether these results suggest the existence of a new cdk1-related kinase, possibly involved in the regulation of early development. The presence of this kinase in all organisms investigated so far, from plants to mammals, calls for its definitive identification.
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Affiliation(s)
- L Détivaud
- CNRS, Station Biologique, Roscoff, France
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43
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Zhang Q, Wang X, Wolgemuth DJ. Developmentally regulated expression of cyclin D3 and its potential in vivo interacting proteins during murine gametogenesis. Endocrinology 1999; 140:2790-800. [PMID: 10342870 DOI: 10.1210/endo.140.6.6756] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To begin to assess the function of the cell cycle regulator cyclin D3 during gametogenesis, the present study examined its expression, interacting partners, and associated kinase activity in the murine testis and ovary. In the early stages of postnatal testicular development, cyclin D3 protein was detected in spermatogonia and Leydig cells. In the adult testis, cyclin D3 was also expressed in terminally differentiating spermatids. In the embryonic ovary, detection of cyclin D3 was limited to somatic cells. In the postnatal ovary, its localization was predominantly in the nuclei of oocytes in primordial and small follicles, a localization that diminished with oocyte growth. Cdk4 and p27 were expressed in a similar subset of testicular and ovarian cells, suggesting that they may regulate cyclin D3 function during testicular and ovarian development in a cell type-specific manner. Cyclin D3-associated kinase activity was detected in immature, but not adult, testes and ovaries. These observations suggest unique roles for cyclin D3 in the control of cell division and differentiation in the germ line and the differential regulation of mitotic and meiotic cell cycles during male and female gametogenesis.
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Affiliation(s)
- Q Zhang
- Center for Reproductive Sciences, and Institute of Human Nutrition, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA
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44
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Abstract
Hypothesizing that genes important in meiotic processes in mammals might have evolutionarily conserved counterparts in lower organisms, we used the yeast IME2 meiotic gene (serine threonine kinase) as a probe for screening a mouse testis cDNA library. This screening resulted in identification of a novel putative serine threonine kinase. Although it did not exhibit significant homology to IME2, it did show significant sequence homology to the Tousled kinase in Arabidopsis. Tousled is associated with various differentiative processes including differentiation of the reproductive organs. The new murine gene was designated accordingly Tlk (Tousled like kinase). Tousled like kinase sequences have been reported to occur in C. elegans and in the human. Positive hybridization signals obtained in zooblot analysis suggest evolutionary conservation of Tlk throughout the phylogenetic ladder. Four distinct Tlk transcripts were detected in mouse testis, at least one of which is testis-specific. Northern and in situ hybridization analyses revealed that in normal testis, Tlk is expressed predominantly in pachytene spermatocytes and in round spermatids. Transcripts differ from one another in their 3' untranslated region, resulting from use of different polyadenylation sites, and in the length of their 5' region. Within the coding region, three of the putative peptides share the kinase and C-terminal domains but differ in their N-terminal domain, suggesting that the latter may be involved in the regulation of Tlk's function. We conclude that although Tlk might have an essential role in all tissues, these kinases are likely to take part in the complex array of phosphorylations involved in regulating spermatogenesis.
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Affiliation(s)
- S Shalom
- Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
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45
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Ravnik SE, Wolgemuth DJ. Regulation of meiosis during mammalian spermatogenesis: the A-type cyclins and their associated cyclin-dependent kinases are differentially expressed in the germ-cell lineage. Dev Biol 1999; 207:408-18. [PMID: 10068472 DOI: 10.1006/dbio.1998.9156] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To begin to examine the function of the A-type cyclins during meiosis in the male, we have examined the developmental and cellular distribution of the cyclin A1 and cyclin A2 proteins, as well as their candidate cyclin-dependent kinase partners, Cdk1 and Cdk2, in the spermatogenic lineage. Immunohistochemical localization revealed that cyclin A1 is present only in male germ cells just prior to or during the first, but not the second, meiotic division. By contrast, cyclin A2 was expressed in spermatogonia and was most abundant in preleptotene spermatocytes, cells which will enter the meiotic pathway. Immunohistochemical detection of Cdk1 was most apparent in early pachytene spermatocytes, while staining intensity diminished in diplotene and meiotically dividing spermatocytes, the cells in which cyclin A1 expression was strongest. Cdk2 was highly expressed in all spermatocytes. Notably, in cells undergoing the meiotic reduction divisions, Cdk2 appeared to localize specifically to the chromatin. This was not the case for spermatogonia undergoing mitotic divisions. In the testis, cyclin A1 has been shown to bind both Cdk1 and Cdk2 but we show here that cyclin A2 binds only Cdk2. These results indicate that the A-type cyclins and their associated kinases have different functions in the initiation and passage of male germ cells through meiosis.
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Affiliation(s)
- S E Ravnik
- Department of Cell Biology & Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas, 79430, USA
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Rhee K, Brunori M, Besset V, Trousdale R, Wolgemuth DJ. Expression and potential role of Fsrg1, a murine bromodomain-containing homologue of the Drosophila gene female sterile homeotic. J Cell Sci 1998; 111 ( Pt 23):3541-50. [PMID: 9811568 DOI: 10.1242/jcs.111.23.3541] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have isolated a cDNA which is a murine homologue of the Drosophila gene female sterile homeotic (fsh). This homologue, which we have designated Fsrg1*, contains two bromodomains and an ET motif characteristic of the Fsh sub-class of bromodomain-containing proteins. Northern blot hybridization analysis of adult tissues revealed that Fsrg1 was expressed at low levels rather ubiquitously, but most abundantly in the testis and ovary. Polyclonal antibodies raised against an Fsrg1 fusion protein were used to characterize the Fsrg1 gene product in tissues. Constructs were also generated in which the Fsrg1 cDNA was tagged with epitopes for hemaglutinin and used in transfection experiments. Immunoblot analysis revealed that the Fsrg1 protein migrates with a relative molecular mass of approximately 110 kDa, although the cDNA sequence would predict a protein of approximately 88 kDa. The migration at approximately 110 kDa was observed for both in vivo protein and protein produced in cultured cells. The Fsrg1 protein was localized to the nucleus when expressed in cultured cells, consistent with the presence of a nuclear localization signal motif in the Fsrg1 sequence. No kinase activity was detected for this nuclear protein as assessed in either autokinase or specific substrate assays. In situ hybridization analysis revealed strikingly high expression of Fsrg1 in granulosa cells of growing follicles in the adult ovary and suggested its possible involvement in folliculogenesis. Additional clues to its potential function were provided by the demonstration of its high level of expression in epithelia of tissues which undergo hormonally-modulated remodeling.
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Affiliation(s)
- K Rhee
- Department of Genetics & Development, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
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Hoyer-Fender S, Petersen C, Brohmann H, Rhee K, Wolgemuth DJ. Mouse Odf2 cDNAs consist of evolutionary conserved as well as highly variable sequences and encode outer dense fiber proteins of the sperm tail. Mol Reprod Dev 1998; 51:167-75. [PMID: 9740324 DOI: 10.1002/(sici)1098-2795(199810)51:2<167::aid-mrd6>3.0.co;2-o] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The outer dense fibers (ODF) of the mammalian sperm tail comprise a unique, specialized, and very prominent structure, consisting of nine fibers surrounding the axoneme. The ODF may play an important but as yet undefined role in sperm morphology, integrity and function. Study of the ODF is hampered by insufficient knowledge of their protein composition and the genetic regulation of their synthesis. We report here on the characterization of cDNAs encoding the Odf2 proteins of outer dense fibers of mouse sperm. We isolated two cDNA clones with variable 5' regions. Variability in sequence is restricted to specific regions in the N-terminal part of the encoded proteins, whereas the C-terminal part is highly conserved in Odf2 proteins both between species and within a species. This variability is confirmed at the protein level. The outer dense fibers could be detected immunologically in total sperm tails allowing a direct comparison of their length in relation to the length of the sperm tail. Odf2 transcripts could be demonstrated in testicular RNA and are restricted to germ cells. The start of transcription is in step 5 spermatids of tubular stage V and the RNA could be detected in the cytoplasm of differentiating spermatids in all subsequent tubular stages.
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Affiliation(s)
- S Hoyer-Fender
- University of Göttingen, III. Department of Zoology-Developmental Biology, Germany
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Robker RL, Richards JS. Hormonal control of the cell cycle in ovarian cells: proliferation versus differentiation. Biol Reprod 1998; 59:476-82. [PMID: 9716543 DOI: 10.1095/biolreprod59.3.476] [Citation(s) in RCA: 165] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Affiliation(s)
- R L Robker
- Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030, USA
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Besset V, Rhee K, Wolgemuth DJ. The identification and characterization of expression of Pftaire-1, a novel Cdk family member, suggest its function in the mouse testis and nervous system. Mol Reprod Dev 1998; 50:18-29. [PMID: 9547506 DOI: 10.1002/(sici)1098-2795(199805)50:1<18::aid-mrd3>3.0.co;2-#] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We have isolated a murine cDNA encoding for a novel putative Cdk-related protein kinase, which has been named Pftaire-1, by screening a testis cDNA library for new serine/threonine kinases. Pftaire-1 showed 50% and 49% amino acid identity with Cdk5 and Pctaire-3, respectively, and contains the eleven subdomains characteristic of the protein kinases. By northern blot analysis we detected two transcripts of approximately 5.5 and 4.9 kb in size. These transcripts were expressed at low level in all murine tissues tested, except in the brain, testis and embryo, where high expression was detected. Cellular localization of the mRNAs by in situ hybridization analysis shows that Pftaire-1 is expressed in late pachytene spermatocytes in the testis and in post mitotic neuronal cells both in the brain and the embryo, suggesting a role of Pftaire-1 both in the process of meiosis as well as neuron differentiation and/or function.
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Affiliation(s)
- V Besset
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
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