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

• Published in: Science (American Association for the Advancement of Science) 2001-03, Vol.291 (5513), p.2603-2605
• Main Authors: Gatesy, John, Hayashi, Cheryl, Motriuk, Dagmara, Woods, Justin, Lewis, Randolph
• Format: Article
• Language: English
• Subjects: Amino Acid Motifs; Amino Acid Sequence; Amino acids; Animal glands; Animals; Arachnids; Araneae; Biological and medical sciences; Biological evolution; Complementary DNA; Composition; Conserved Sequence; DNA, Complementary; Evolution, Molecular; fibroin; Fibroins - chemistry; Fibroins - genetics; Fundamental and applied biological sciences. Psychology; Genetic aspects; Genetics of eukaryotes. Biological and molecular evolution; Insect Proteins - chemistry; Lepidoptera - chemistry; Libraries; Molecular biology; Molecular Sequence Data; Molecules; Nucleotide sequences; Phylogenetics; Phylogeny; Proteins; Proteins - chemistry; Proteins - genetics; Repetitive Sequences, Amino Acid; Sequence Alignment; Silk; Silk glands; Species Specificity; Spider webs; Spiders; Spiders - chemistry; Spiders - classification; Spiders - genetics; Taxa; Tensile Strength
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1057561

Spiders (Araneae) spin high-performance silks from liquid fibroin proteins. Fibroin sequences from basal spider lineages reveal mosaics of amino acid motifs that differ radically from previously described spider silk sequences. The silk fibers of Araneae are constructed from many protein designs. Yet, the repetitive sequences of fibroins from orb-weaving spiders have been maintained, presumably by stabilizing selection, over 125 million years of evolutionary history. The retention of these conserved motifs since the Mesozoic and their convergent evolution in other structural superproteins imply that these sequences are central to understanding the exceptional mechanical properties of orb weaver silks.