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Correa-Garhwal SM, Baker RH, Clarke TH, Ayoub NA, Hayashi CY. The evolutionary history of cribellate orb-weaver capture thread spidroins. BMC Ecol Evol 2022; 22:89. [PMID: 35810286 PMCID: PMC9270836 DOI: 10.1186/s12862-022-02042-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 06/21/2022] [Indexed: 11/19/2022] Open
Abstract
Background Spiders have evolved two types of sticky capture threads: one with wet adhesive spun by ecribellate orb-weavers and another with dry adhesive spun by cribellate spiders. The evolutionary history of cribellate capture threads is especially poorly understood. Here, we use genomic approaches to catalog the spider-specific silk gene family (spidroins) for the cribellate orb-weaver Uloborus diversus. Results We show that the cribellar spidroin, which forms the puffy fibrils of cribellate threads, has three distinct repeat units, one of which is conserved across cribellate taxa separated by ~ 250 Mya. We also propose candidates for a new silk type, paracribellar spidroins, which connect the puffy fibrils to pseudoflagelliform support lines. Moreover, we describe the complete repeat architecture for the pseudoflagelliform spidroin (Pflag), which contributes to extensibility of pseudoflagelliform axial fibers. Conclusions Our finding that Pflag is closely related to Flag, supports homology of the support lines of cribellate and ecribellate capture threads. It further suggests an evolutionary phase following gene duplication, in which both Flag and Pflag were incorporated into the axial lines, with subsequent loss of Flag in uloborids, and increase in expression of Flag in ecribellate orb-weavers, explaining the distinct mechanical properties of the axial lines of these two groups. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-022-02042-5.
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2
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Correa-Garhwal SM, Babb PL, Voight BF, Hayashi CY. Golden orb-weaving spider (Trichonephila clavipes) silk genes with sex-biased expression and atypical architectures. G3 (Bethesda) 2021; 11:6044138. [PMID: 33561241 PMCID: PMC8022711 DOI: 10.1093/g3journal/jkaa039] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 12/05/2020] [Indexed: 11/29/2022]
Abstract
Spider silks are renowned for their high-performance mechanical properties. Contributing to these properties are proteins encoded by the spidroin (spider fibroin) gene family. Spidroins have been discovered mostly through cDNA studies of females based on the presence of conserved terminal regions and a repetitive central region. Recently, genome sequencing of the golden orb-web weaver, Trichonephila clavipes, provided a complete picture of spidroin diversity. Here, we refine the annotation of T. clavipes spidroin genes including the reclassification of some as non-spidroins. We rename these non-spidroins as spidroin-like (SpL) genes because they have repetitive sequences and amino acid compositions like spidroins, but entirely lack the archetypal terminal domains of spidroins. Insight into the function of these spidroin and SpL genes was then examined through tissue- and sex-specific gene expression studies. Using qPCR, we show that some silk genes are upregulated in male silk glands compared to females, despite males producing less silk in general. We also find that an enigmatic spidroin that lacks a spidroin C-terminal domain is highly expressed in silk glands, suggesting that spidroins could assemble into fibers without a canonical terminal region. Further, we show that two SpL genes are expressed in silk glands, with one gene highly evolutionarily conserved across species, providing evidence that particular SpL genes are important to silk production. Together, these findings challenge long-standing paradigms regarding the evolutionary and functional significance of the proteins and conserved motifs essential for producing spider silks.
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Affiliation(s)
- Sandra M Correa-Garhwal
- Division of Invertebrate Zoology and Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
| | - Paul L Babb
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Benjamin F Voight
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.,Institute for Translational Medicine and Therapeutics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Cheryl Y Hayashi
- Division of Invertebrate Zoology and Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
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3
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Ayoub NA, Friend K, Clarke T, Baker R, Correa-Garhwal SM, Crean A, Dendev E, Foster D, Hoff L, Kelly SD, Patterson W, Hayashi CY, Opell BD. Protein composition and associated material properties of cobweb spiders' gumfoot glue droplets. Integr Comp Biol 2021; 61:1459-1480. [PMID: 34003260 PMCID: PMC8631074 DOI: 10.1093/icb/icab086] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The origin of aggregate silk glands and their production of wet adhesive silks is considered a key innovation of the Araneoidea, a superfamily of spiders that build orb-webs and cobwebs. Orb-web weavers place aggregate glue on an extensible capture spiral, whereas cobweb weavers add it to the ends of strong, stiff fibers, called gumfoot lines. Here we describe the material behavior and quantitative proteomics of the aggregate glues of two cobweb weaving species, the western black widow, Latrodectus hesperus, and the common house spider, Parasteatoda tepidariorum. For each species, respectively, we identified 48 and 33 proteins that were significantly more abundant in the portion of the gumfoot line with glue than in its fibers. These proteins were more highly glycosylated and phosphorylated than proteins found in silk fibers without glue, which likely explains aggregate glue stickiness. Most glue-enriched proteins were of anterior aggregate gland origin, supporting the hypothesis that cobweb weavers’ posterior aggregate glue is specialized for another function. We found that cobweb weaver glue droplets are stiffer and tougher than the adhesive of most orb-web weaving species. Attributes of gumfoot glue protein composition that likely contribute to this stiffness include the presence of multiple protein families with conserved cysteine residues, a bimodal distribution of isoelectric points, and families with conserved functions in protein aggregation, all of which should contribute to cohesive protein–protein interactions. House spider aggregate droplets were more responsive to humidity changes than black widow droplets, which could be mediated by differences in protein sequence, post-translational modifications, the non-protein components of the glue droplets, and/or the larger amount of aqueous material that surrounds the adhesive cores of their glue droplets.
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Affiliation(s)
- Nadia A Ayoub
- Department of Biology, Washington and Lee University, Lexington, VA 24450, USA
- E-mail:
| | - Kyle Friend
- Department of Chemistry and Biochemistry, Washington and Lee University, Lexington, VA 24450, USA
| | - Thomas Clarke
- Department of Biology, Washington and Lee University, Lexington, VA 24450, USA
| | - Richard Baker
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
| | - Sandra M Correa-Garhwal
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
| | - Andrew Crean
- Department of Biology, Washington and Lee University, Lexington, VA 24450, USA
| | - Enkhbileg Dendev
- Department of Biology, Washington and Lee University, Lexington, VA 24450, USA
- Department of Chemistry and Biochemistry, Washington and Lee University, Lexington, VA 24450, USA
| | - Delaney Foster
- Department of Biology, Washington and Lee University, Lexington, VA 24450, USA
| | - Lorden Hoff
- Department of Biology, Washington and Lee University, Lexington, VA 24450, USA
| | - Sean D Kelly
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA
- Joint Department of Evolutionary Biology, San Diego State University and University of California Riverside, San Diego, CA 92182, USA
| | - Wade Patterson
- Department of Biology, Washington and Lee University, Lexington, VA 24450, USA
| | - Cheryl Y Hayashi
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA
| | - Brent D Opell
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA
- E-mail:
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4
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Dugger TW, Sarkar S, Correa-Garhwal SM, Zhernenkov M, Zhang Y, Kolhatkar G, Mohan R, Cruz L, Lubio AD, Ruediger A, Hayashi CY, Uhrich KE, Kisailus DJ. Ultrastructures and Mechanics of Annealed Nephila clavipes Major Ampullate Silk. Biomacromolecules 2020; 21:1186-1194. [PMID: 32003982 DOI: 10.1021/acs.biomac.9b01615] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The semicrystalline protein structure and impressive mechanical properties of major ampullate (MA) spider silk make it a promising natural alternative to polyacrylonitrile (PAN) fibers for carbon fiber manufacture. However, when annealed using a similar procedure to carbon fiber production, the tensile strength and Young's modulus of MA silk decrease. Despite this, MA silk fibers annealed at 600 °C remain stronger and tougher than similarly annealed PAN but have a lower Young's modulus. Although MA silk and PAN graphitize to similar extents, annealing disrupts the hydrogen bonding that controls crystal alignment within MA silk. Consequently, unaligned graphite crystals form in annealed MA silk, causing it to weaken, while graphite crystals in PAN maintain alignment along the fiber axis, strengthening the fibers. These shortcomings of spider silk when annealed provide insights into the selection and design of future alternative carbon fiber precursors.
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Affiliation(s)
- Thomas W Dugger
- Materials Science and Engineering Program, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States
| | - Sourangsu Sarkar
- Department of Chemical and Environmental Engineering, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States
| | - Sandra M Correa-Garhwal
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States
| | - Mikhail Zhernenkov
- National Synchrotron Light Source II, Brookhaven National Laboratory, 743 Brookhaven Avenue, Upton, New York 11973-5000, United States
| | - Yugang Zhang
- National Synchrotron Light Source II, Brookhaven National Laboratory, 743 Brookhaven Avenue, Upton, New York 11973-5000, United States
| | - Gitanjali Kolhatkar
- Nanoelectronics-Nanophotonics, Institut National de la Recherche Scientifique, Université du Québec, 1650, Boul. Lionel-Boulet, Varennes J3X1S2, Québec, Canada
| | - Ramya Mohan
- Materials Science and Engineering Program, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States
| | - Luz Cruz
- Materials Science and Engineering Program, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States
| | - Aura D Lubio
- Nanoelectronics-Nanophotonics, Institut National de la Recherche Scientifique, Université du Québec, 1650, Boul. Lionel-Boulet, Varennes J3X1S2, Québec, Canada
| | - Andreas Ruediger
- Nanoelectronics-Nanophotonics, Institut National de la Recherche Scientifique, Université du Québec, 1650, Boul. Lionel-Boulet, Varennes J3X1S2, Québec, Canada
| | - Cheryl Y Hayashi
- Materials Science and Engineering Program, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States.,Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States.,Division of Invertebrate Zoology and Sackler Institute for Comparative Genomics, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024-5192, United States
| | - Kathryn E Uhrich
- Materials Science and Engineering Program, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States.,Department of Chemistry, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States
| | - David J Kisailus
- Materials Science and Engineering Program, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States.,Department of Chemical and Environmental Engineering, University of California, Riverside, 900 University Ave, Riverside, California 92521, United States
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5
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Correa-Garhwal SM, Clarke TH, Janssen M, Crevecoeur L, McQuillan BN, Simpson AH, Vink CJ, Hayashi CY. Spidroins and Silk Fibers of Aquatic Spiders. Sci Rep 2019; 9:13656. [PMID: 31541123 PMCID: PMC6754431 DOI: 10.1038/s41598-019-49587-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 08/24/2019] [Indexed: 12/21/2022] Open
Abstract
Spiders are commonly found in terrestrial environments and many rely heavily on their silks for fitness related tasks such as reproduction and dispersal. Although rare, a few species occupy aquatic or semi-aquatic habitats and for them, silk-related specializations are also essential to survive in aquatic environments. Most spider silks studied to date are from cob-web and orb-web weaving species, leaving the silks from many other terrestrial spiders as well as water-associated spiders largely undescribed. Here, we characterize silks from three Dictynoidea species: the aquatic spiders Argyroneta aquatica and Desis marina as well as the terrestrial Badumna longinqua. From silk gland RNA-Seq libraries, we report a total of 47 different homologs of the spidroin (spider fibroin) gene family. Some of these 47 spidroins correspond to known spidroin types (aciniform, ampullate, cribellar, pyriform, and tubuliform), while other spidroins represent novel branches of the spidroin gene family. We also report a hydrophobic amino acid motif (GV) that, to date, is found only in the spidroins of aquatic and semi-aquatic spiders. Comparison of spider silk sequences to the silks from other water-associated arthropods, shows that there is a diversity of strategies to function in aquatic environments.
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Affiliation(s)
- Sandra M Correa-Garhwal
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, 92591, USA.
| | - Thomas H Clarke
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, 92591, USA
- J. Craig Venter Institute, Rockville, MD, 28050, USA
| | | | - Luc Crevecoeur
- Limburg Dome for Nature Study, Provincial Nature Center, Genk, 3600, Belgium
| | | | | | - Cor J Vink
- Canterbury Museum, Christchurch, 8013, New Zealand
| | - Cheryl Y Hayashi
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, 92591, USA
- Division of Invertebrate Zoology and Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY, 10024, USA
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6
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Correa-Garhwal SM, Chaw RC, Dugger T, Clarke TH, Chea KH, Kisailus D, Hayashi CY. Semi-aquatic spider silks: transcripts, proteins, and silk fibres of the fishing spider, Dolomedes triton (Pisauridae). Insect Mol Biol 2019; 28:35-51. [PMID: 30059178 DOI: 10.1111/imb.12527] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
To survive in terrestrial and aquatic environments, spiders often rely heavily on their silk. The vast majority of silks that have been studied are from orb-web or cob-web weaving species, leaving the silks of water-associated spiders largely undescribed. We characterize transcripts, proteins, and silk fibres from the semi-aquatic spider Dolomedes triton. From silk gland RNAseq libraries, we report 18 silk transcripts representing four categories of known silk protein types: aciniform, ampullate, pyriform, and tubuliform. Proteomic and structural analyses (scanning electron microscopy, energy dispersive X-ray spectrometry, contact angle) of the D. triton submersible egg sac reveal similarities to silks from aquatic caddisfly larvae. We identified two layers in D. triton egg sacs, notably a highly hydrophobic outer layer with a different elemental composition compared to egg sacs of terrestrial spiders. These features may provide D. triton egg sacs with their water repellent properties.
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Affiliation(s)
- S M Correa-Garhwal
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, USA
| | - R C Chaw
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, USA
- Department of Neurology, Oregon Health and Science University, Portland, OR, USA
| | - T Dugger
- Materials Science and Engineering Program, University of California, Riverside, CA, USA
| | - T H Clarke
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, USA
- J. Craig Venter Institute, Rockville, MD, USA
| | - K H Chea
- Materials Science and Engineering Program, University of California, Riverside, CA, USA
| | - D Kisailus
- Materials Science and Engineering Program, University of California, Riverside, CA, USA
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA, USA
| | - C Y Hayashi
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, USA
- Division of Invertebrate Zoology and Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY, USA
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7
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Correa-Garhwal SM, Chaw RC, Clarke TH, Ayoub NA, Hayashi CY. Silk gene expression of theridiid spiders: implications for male-specific silk use. ZOOLOGY 2017; 122:107-114. [PMID: 28536006 DOI: 10.1016/j.zool.2017.04.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 04/21/2017] [Accepted: 04/21/2017] [Indexed: 01/15/2023]
Abstract
Spiders (order Araneae) rely on their silks for essential tasks, such as dispersal, prey capture, and reproduction. Spider silks are largely composed of spidroins, members of a protein family that are synthesized in silk glands. As needed, silk stored in silk glands is extruded through spigots on the spinnerets. Nearly all studies of spider silks have been conducted on females; thus, little is known about male silk biology. To shed light on silk use by males, we compared silk gene expression profiles of mature males to those of females from three cob-web weaving species (Theridiidae). We de novo assembled species-specific male transcriptomes from Latrodectus hesperus, Latrodectus geometricus, and Steatoda grossa followed by differential gene expression analyses. Consistent with their complement of silk spigots, male theridiid spiders express appreciable amounts of aciniform, major ampullate, minor ampullate, and pyriform spidroin genes but not tubuliform spidroin genes. The relative expression levels of particular spidroin genes varied between sexes and species. Because mature males desert their prey-capture webs and become cursorial in their search for mates, we anticipated that major ampullate (dragline) spidroin genes would be the silk genes most highly expressed by males. Indeed, major ampullate spidroin genes had the highest expression in S. grossa males. However, minor ampullate spidroin genes were the most highly expressed spidroin genes in L. geometricus and L. hesperus males. Our expression profiling results suggest species-specific adaptive divergence of silk use by male theridiids.
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Affiliation(s)
| | - R Crystal Chaw
- Department of Biology, University of California, Riverside, CA 92521, USA.
| | - Thomas H Clarke
- Department of Biology, University of California, Riverside, CA 92521, USA; Department of Biology, Washington and Lee University, Lexington, VA 24450, USA; J. Craig Venter Institute, Rockville, MD 20850, USA.
| | - Nadia A Ayoub
- Department of Biology, Washington and Lee University, Lexington, VA 24450, USA.
| | - Cheryl Y Hayashi
- Department of Biology, University of California, Riverside, CA 92521, USA; Division of Invertebrate Zoology, American Museum of Natural History, New York, NY 10024, USA.
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Vienneau-Hathaway JM, Brassfield ER, Lane AK, Collin MA, Correa-Garhwal SM, Clarke TH, Schwager EE, Garb JE, Hayashi CY, Ayoub NA. Duplication and concerted evolution of MiSp-encoding genes underlie the material properties of minor ampullate silks of cobweb weaving spiders. BMC Evol Biol 2017; 17:78. [PMID: 28288560 PMCID: PMC5348893 DOI: 10.1186/s12862-017-0927-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 02/24/2017] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Orb-web weaving spiders and their relatives use multiple types of task-specific silks. The majority of spider silk studies have focused on the ultra-tough dragline silk synthesized in major ampullate glands, but other silk types have impressive material properties. For instance, minor ampullate silks of orb-web weaving spiders are as tough as draglines, due to their higher extensibility despite lower strength. Differences in material properties between silk types result from differences in their component proteins, particularly members of the spidroin (spider fibroin) gene family. However, the extent to which variation in material properties within a single silk type can be explained by variation in spidroin sequences is unknown. Here, we compare the minor ampullate spidroins (MiSp) of orb-weavers and cobweb weavers. Orb-web weavers use minor ampullate silk to form the auxiliary spiral of the orb-web while cobweb weavers use it to wrap prey, suggesting that selection pressures on minor ampullate spidroins (MiSp) may differ between the two groups. RESULTS We report complete or nearly complete MiSp sequences from five cobweb weaving spider species and measure material properties of minor ampullate silks in a subset of these species. We also compare MiSp sequences and silk properties of our cobweb weavers to published data for orb-web weavers. We demonstrate that all our cobweb weavers possess multiple MiSp loci and that one locus is more highly expressed in at least two species. We also find that the proportion of β-spiral-forming amino acid motifs in MiSp positively correlates with minor ampullate silk extensibility across orb-web and cobweb weavers. CONCLUSIONS MiSp sequences vary dramatically within and among spider species, and have likely been subject to multiple rounds of gene duplication and concerted evolution, which have contributed to the diverse material properties of minor ampullate silks. Our sequences also provide templates for recombinant silk proteins with tailored properties.
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Affiliation(s)
| | | | - Amanda Kelly Lane
- Department of Biology, Washington and Lee University, Lexington, VA USA
| | | | | | - Thomas H. Clarke
- Department of Biology, Washington and Lee University, Lexington, VA USA
- Department of Biology, University of California, Riverside, CA USA
| | - Evelyn E. Schwager
- Department of Biological Sciences, University of Massachusetts, Lowell, MA USA
| | - Jessica E. Garb
- Department of Biological Sciences, University of Massachusetts, Lowell, MA USA
| | | | - Nadia A. Ayoub
- Department of Biology, Washington and Lee University, Lexington, VA USA
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9
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Abstract
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Spider
silk research has largely focused on spidroins, proteins
that are the primary components of spider silk fibers. Although a
number of spidroins have been characterized, other types of proteins
associated with silk synthesis are virtually unknown. Previous analyses
of tissue-specific RNA-seq libraries identified 647 predicted genes
that were differentially expressed in silk glands of the Western black
widow, Latrodectus hesperus. Only ∼5%
of these silk-gland specific transcripts (SSTs) encode spidroins;
although the remaining predicted genes presumably encode other proteins
associated with silk production, this is mostly unverified. Here,
we used proteomic analysis of multiple silk glands and dragline silk
fiber to investigate the translation of the differentially expressed
genes. We find 48 proteins encoded by the differentially expressed
transcripts in L. hesperus major ampullate,
minor ampullate, and tubuliform silk glands and detect 17 SST encoded
proteins in major ampullate silk fibers. The observed proteins include
known silk-related proteins, but most are uncharacterized, with no
annotation. These unannotated proteins likely include novel silk-associated
proteins. Major and minor ampullate glands have the highest overlap
of identified proteins, consistent with their shared, distinctive
ampullate shape and the overlapping functions of major and minor ampullate
silks. Our study substantiates and prioritizes predictions from differential
expression analysis of spider silk gland transcriptomes.
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Affiliation(s)
- Ro Crystal Chaw
- Department of Biology, University of California , Riverside, California 92521, United States
| | - Sandra M Correa-Garhwal
- Department of Biology, University of California , Riverside, California 92521, United States
| | - Thomas H Clarke
- Department of Biology, Washington and Lee University , Lexington, Virginia 24450, United States
| | - Nadia A Ayoub
- Department of Biology, Washington and Lee University , Lexington, Virginia 24450, United States
| | - Cheryl Y Hayashi
- Department of Biology, University of California , Riverside, California 92521, United States
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Correa-Garhwal SM, Garb JE. Diverse Formulas for Spider Dragline Fibers Demonstrated by Molecular and Mechanical Characterization of Spitting Spider Silk. Biomacromolecules 2014; 15:4598-605. [DOI: 10.1021/bm501409n] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Sandra M. Correa-Garhwal
- Department of Biological
Sciences, University of Massachusetts—Lowell, Lowell, Massachusetts 01854, United States
| | - Jessica E. Garb
- Department of Biological
Sciences, University of Massachusetts—Lowell, Lowell, Massachusetts 01854, United States
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