Related Experiment Video
Updated: Jul 31, 2026

Microdissection of Black Widow Spider Silk-producing Glands
Published on: January 11, 2011
Spider flagelliform silk: lessons in protein design, gene structure, and molecular evolution
1Department of Molecular Biology, University of Wyoming, Laramie, USA. chayashi@citrus.ucr.edu
Abstract:
Spiders spin multiple types of silks that are renowned for their superb mechanical properties. Flagelliform silk, used in the capture spiral of an orb-web, is one of the few silks characterized by both cDNA and genomic DNA data. This fibroin is composed of repeating ensembles of three types of amino acid sequence motifs. The predominant subrepeat, GPGGX, likely forms a beta-turn, and tandem arrays of these turns are thought to create beta-spirals. These spring-like helices may be critical for the exceptional ability of capture silk to stretch and recoil. Each ensemble of motifs was found to correspond to a different exon within the flagelliform gene. The pattern of sequence similarity among exons indicates intragenic concerted evolution. Surprisingly, the introns between the iterated exons are also homogenized with each other. This unusual molecular architecture in the flagelliform silk gene has implications for the evolution and maintenance of spider silk proteins.
Related Concept Videos
Protein and Protein Structure
A protein's shape is critical to its function. For example, an enzyme can...
Conservation of Protein Domains Over Different Proteins
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
Globular and Fibrous Proteins
Globular proteins are also known as spheroproteins and typically are approximately round in shape. They contain a mix of amino acid types and contain differing sequences in their primary structures. Globular proteins have many different functions, such as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be...
The Structure of Intermediate Filaments
Intermediate filaments...
Globular and Fibrous Proteins
Globular proteins are also known as spheroproteins and typically are approximately round in shape. They contain a mix of amino acid types and contain differing sequences in their primary structures. Globular proteins have many different functions, such as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be...
Fibrous Proteins

