Modular evolution of egg case silk genes across orb-weaving spider superfamilies.

@article{Garb2005ModularEO,
  title={Modular evolution of egg case silk genes across orb-weaving spider superfamilies.},
  author={Jessica E. Garb and Cheryl Y. Hayashi},
  journal={Proceedings of the National Academy of Sciences of the United States of America},
  year={2005},
  volume={102 32},
  pages={
          11379-84
        }
}
  • Jessica E. Garb, C. Hayashi
  • Published 9 August 2005
  • Biology
  • Proceedings of the National Academy of Sciences of the United States of America
Spider silk proteins (fibroins) are renowned for their extraordinary mechanical properties and biomimetic potential. Despite extensive evolutionary, ecological, and industrial interest in these fibroins, only a fraction of the known silk types have been characterized at the molecular level. Here we report cDNA and genomic sequences of the fibroin TuSp1, which appears to be the major component of tubuliform gland silk, a fiber exclusively synthesized by female spiders for egg case construction… 

Figures and Tables from this paper

The Nephila clavipes genome highlights the diversity of spider silk genes and their complex expression

TLDR
This work constructed the first genome of an orb-weaving spider: the golden orb- weaver (Nephila clavipes), which builds large webs using an extensive repertoire of silks with diverse physical properties, and identifies 394 repeated coding motif variants and higher-order repetitive cassette structures unique to specific spidroins.

Early Events in the Evolution of Spider Silk Genes

TLDR
A surprisingly rich silk gene diversity is uncovered from the silk glands of six mygalomorph species, a mesothele, and a non-orbicularian araneomorph, and in particular, ECP homologs are found in the mesothle, suggesting that ECPs were present in the common ancestor of extant spiders, and originally were not specialized to complex with tubuliform spidroins.

Untangling spider silk evolution with spidroin terminal domains

TLDR
A non-repetitive N-terminal domain appears to be a universal attribute of spidroin proteins, likely retained from the origin of spider silk production, and combined analysis produces the most resolved trees.

Mosaic Evolution of Silk Genes in Aliatypus Trapdoor Spiders (Mygalomorphae, Antrodiaetidae)

TLDR
It is found that purifying selection and concerted evolution have acted to conserve Aliatypus spidroin internal repetitive regions, and selection testing identifies evidence of sites that evolved under positive selection and amino acid replacements that result in radical physicochemical changes in the carboxy terminal region.

Egg Case Silk Gene Sequences from Argiope Spiders: Evidence for Multiple Loci and a Loss of Function Between Paralogs

TLDR
It is demonstrated that the silver garden spider Argiope argentata has multiple egg case spidroin loci with a loss of function at one locus, consistent with concerted evolution homogenizing gene copies within a genome.

Protein families, natural history and biotechnological aspects of spider silk.

TLDR
This review presents descriptions of members from each family of spidroin identified from five spider species of the Brazilian biodiversity, and an evolutionary study of them in correlation with the anatomical specialization of glands and spider's spinning behaviors.

Molecular Evolution of Lepidopteran Silk Proteins: Insights from the Ghost Moth, Hepialus californicus

TLDR
By characterizing the H. californicus silk fibroins, key functional amino acids are identified and insight is gained into the evolutionary processes that have shaped these adaptive molecules.

Molecular Evolution of Silk Genes in Mesothele and Mygalomorph Spiders, With Implications for the Early Evolution and Functional Divergence of Silk

TLDR
Phylogenetic analyses reveal that despite instances of lineage specific duplication and loss of hemocyanin paralogs, hemOCyanins have phylogenetic utility for most spider groups.
...

References

SHOWING 1-10 OF 41 REFERENCES

Analysis of major ampullate silk cDNAs from two non-orb-weaving spiders.

TLDR
Four partial cDNA clones representing major ampullate spider silk gene transcripts from two non-orb weavers are isolated and sequenced, indicating that the repeats encoding conserved amino acid motifs that are characteristic of some orb-weaving spider silks are also found in some of the cDNAs reported in this study.

Molecular and mechanical characterization of aciniform silk: uniformity of iterated sequence modules in a novel member of the spider silk fibroin gene family.

TLDR
Comparisons of stress/strain curves for major ampullate, minor ampullates, and aciniform silks from Argiope trifasciata showed significant differences in ultimate strength, extensibility, and toughness.

Molecular architecture and evolution of a modular spider silk protein gene.

Spider flagelliform silk is one of the most elastic natural materials known. Extensive sequencing of spider silk genes has shown that the exons and introns of the flagelliform gene underwent

Evidence from flagelliform silk cDNA for the structural basis of elasticity and modular nature of spider silks.

TLDR
It is shown that all spider silk proteins can be characterized as sets of shared structural modules, which suggests that unusual homogenization processes are involved in silk protein evolution.

Extreme Diversity, Conservation, and Convergence of Spider Silk Fibroin Sequences

TLDR
Fibroin sequences from basal spider lineages reveal mosaics of amino acid motifs that differ radically from previously described spider silk sequences, implying that these sequences are central to understanding the exceptional mechanical properties of orb weaver silks.

Evolution of arthropod silks.

  • C. Craig
  • Biology, Medicine
    Annual review of entomology
  • 1997
TLDR
The comparative data and phylogenetic analyses in this review suggest that the silk-secreting systems of spiders and insects are homologous and linked to the crural gland and cuticular secretions of an onychophoran-like ancestor.

Correlation between Fibroin Amino Acid Sequence and Physical Silk Properties*

TLDR
The aim of this research was to relate repeat composition to insect biology and fiber strength, and it is suggested that in the pyralid H-fibroin of pyralids, in these latter two species, variations in the repeat length obstruct repeat alignment, but sufficiently long stretches of iterated residues get superposed to interact.

Egg Case Protein-1

TLDR
Combining matrix-assisted laser desorption ionization tandem time-of-flight mass spectrometry and reverse genetics, a novel gene called ecp-1 is isolated, which encodes for one of the protein components of the 100-kDa species of egg case silk, a new class of silk proteins with distinctive molecular features relative to traditional members of the spider silk gene family.

Special Evolutionary Properties of Genes Encoding a Protein with a Simple Amino Acid Repeat

TLDR
There is evidence that substitutions can alter the mechanisms of unequal crossing-over, altering the way concerted evolution occurs, and an earlier report that Hemicentrotus pulcherrimus fits into the Strongylocentrotus genus is confirmed.