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Spider minor ampullate silk proteins contain new repetitive sequences and highly conserved non-silk-like "spacer regions".

ABSTRACT: Spider minor ampullate silk is a strong non-elastic deformably stretchable silk used in web formation. This silk from Nephila clavipes is composed of two proteins, MiSp 1 and 2, whose transcripts are 9.5 and 7.5 kb, respectively, as determined by Northern blots. Both MiSp proteins are organized into a predominantly repetitive region and a small nonrepetitive carboxy terminal region. These highly repetitive regions are composed mainly of glycine and alanine, but also contain tyrosine, glutamine, and arginine. The sequences are mainly GGX and GA repeats. The repetitive regions are interrupted by nonrepetitive serine-rich spacer regions. Although the sequences of the spacer regions differ from the repetitive regions, sequences of the spacers from different regions of the proteins are nearly identical. The sequence differences between major and minor ampullate silks may explain the differing mechanical properties of the fibers.

SUBMITTER: Colgin MA

PROVIDER: S-EPMC2143960 | biostudies-other | 1998 Mar

REPOSITORIES: biostudies-other

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Spider minor ampullate silk proteins contain new repetitive sequences and highly conserved non-silk-like "spacer regions".

Colgin M A MA Lewis R V RV

Protein science : a publication of the Protein Society 19980301 3

Spider minor ampullate silk is a strong non-elastic deformably stretchable silk used in web formation. This silk from Nephila clavipes is composed of two proteins, MiSp 1 and 2, whose transcripts are 9.5 and 7.5 kb, respectively, as determined by Northern blots. Both MiSp proteins are organized into a predominantly repetitive region and a small nonrepetitive carboxy terminal region. These highly repetitive regions are composed mainly of glycine and alanine, but also contain tyrosine, glutamine, ...[more]

PMID: 9541398

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