Hydrophobic interaction of P25, containing Asn-linked oligosaccharide chains, with the H-L complex of silk fibroin produced by Bombyx mori

Kazunori Tanaka, Satoshi Inoue, Shigeki Mizuno

Research output: Contribution to journalArticlepeer-review

197 Citations (Scopus)

Abstract

Fibroin light (L-) chain and P25 are low molecular weight protein components of silk fibroin which are secreted from the posterior silk gland cells of the silkworm, Bombyx mori. The primary structure of L-chain was determined previously by cDNA cloning and peptide analysis, but that of P25 has only been deduced from its genomic sequence. Our previous studies with specific antibodies against L-chain and P25 have shown that L-chain and H- chain are linked by disulfide bond(s) but P25 is not covalently linked to H- chain. Here, we present evidence that P25 associates with the H-L complex primarily by hydrophobic interactions and that P25 is a glycoprotein containing Asn-linked oligosaccharide chains. From the analysis of three fibroin-secretion-deficient 'naked pupa' mutant breeds [Nd(2), Nd-s and Nd- s(D)], it is suggested that P25 interacts with H-chain in the absence of H-L linkage but its content of oligosaccharide is reduced when the H-L linkage is not formed. From these results, models are presented implying that the HL complex and P25 are associated to form a higher-order complex of specific conformation during the processes of intracellular transport and secretion, and that the Asn-linked glycosylation of P25 is partially altered under such conditions.

Original languageEnglish
Pages (from-to)269-276
Number of pages8
JournalInsect Biochemistry and Molecular Biology
Volume29
Issue number3
DOIs
Publication statusPublished - 1999 Mar
Externally publishedYes

Keywords

  • Bombyx mori
  • Fibroin molecular complex
  • Glycoprotein
  • Hydrophobic interaction
  • P25
  • Secretion-deficient mutants
  • Silk fibroin

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Insect Science

Fingerprint

Dive into the research topics of 'Hydrophobic interaction of P25, containing Asn-linked oligosaccharide chains, with the H-L complex of silk fibroin produced by Bombyx mori'. Together they form a unique fingerprint.

Cite this