Co-expression of BirA with biotin bait achieves in vivo biotinylation of overexpressed stable N-glycosylated sRAGE in transgenic silkworms

Sci Rep. 2017 Mar 23;7(1):356. doi: 10.1038/s41598-017-00420-4.

Abstract

Here, we demonstrated the expression of the N-glycosylated extracellular ligand binding domain of receptor for advanced glycation end products (sRAGE) in middle silk glands (MSGs) of transgenic silkworms using the GAL4/UAS system. Over 1 mg of sRAGE was obtained from one transgenic silkworm. sRAGE purified from the silkworm exhibited good stability and maintained specific ligand-binding ability. In addition, N-glycan analysis of sRAGE revealed that N-glucan completely lacked potentially allergenic fucose. Moreover, co-expression of biotin ligase (BirA) with C-terminal BioEase-tagged sRAGE in MSGs resulted in efficient biotinylation of sRAGE after addition of biotin bait. C-terminal biotinylated sRAGE could be immobilized onto a solid surface in one direction through binding to streptavidin without any loss of ability. The dissociation constant of sRAGE with fructose-BSA, a typical RAGE ligand, was 7.25 × 10-7 M, consistent with that on the mammalian cell surface. Thus, we developed a novel, innovative silkworm expression system for efficient expression of recombinant sRAGE, which could serve as a basis for the elucidation of RAGE-ligand interactions and facilitate the search for new ligands and inhibitors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Biotin / pharmacology*
  • Biotinylation
  • Bombyx / metabolism*
  • Carbon-Nitrogen Ligases / metabolism*
  • Escherichia coli
  • Escherichia coli Proteins / metabolism*
  • Genetic Vectors
  • Humans
  • Receptor for Advanced Glycation End Products / metabolism*
  • Repressor Proteins / metabolism*

Substances

  • Escherichia coli Proteins
  • Receptor for Advanced Glycation End Products
  • Repressor Proteins
  • sRAGE protein, human
  • Biotin
  • Carbon-Nitrogen Ligases
  • birA protein, E coli