RRC ID 55713
Author Ito K, Kidokoro K, Katsuma S, Sezutsu H, Uchino K, Kobayashi I, Tamura T, Yamamoto K, Mita K, Shimada T, Kadono-Okuda K.
Title A single amino acid substitution in the Bombyx-specific mucin-like membrane protein causes resistance to Bombyx mori densovirus.
Journal Sci Rep
Abstract Bombyx mori densovirus type 1 (BmDV) is a pathogen that causes flacherie disease in the silkworm. The absolute nonsusceptibility to BmDV among certain silkworm strains is determined independently by two genes, nsd-1 and Nid-1. However, neither of these genes has been molecularly identified to date. Here, we isolated the nsd-1 gene by positional cloning and characterized the properties of its product, NSD-1. Sequence and biochemical analyses revealed that this gene encodes a Bombyx-specific mucin-like glycoprotein with a single transmembrane domain. The NSD-1 protein was specifically expressed in the larval midgut epithelium, the known infection site of BmDV. Sequence analysis of the nsd-1 gene from 13 resistant and 12 susceptible strains suggested that a specific arginine residue in the extracellular tail of the NSD-1 protein was common among susceptible strains. Germline transformation of the susceptible-type nsd-1 (with a single nucleotide substitution) conferred partial susceptibility to resistant larvae, indicating that the +  nsd-1 gene is required for the susceptibility of B. mori larvae to BmDV and the susceptibility is solely a result of the substitution of a single amino acid with arginine. Taken together, our results provide striking evidence that a novel membrane-bound mucin-like protein functions as a cell-surface receptor for a densovirus.
Volume 8(1)
Pages 7430
Published 2018-5-9
DOI 10.1038/s41598-018-25388-7
PII 10.1038/s41598-018-25388-7
PMID 29743532
PMC PMC5943349
IF 4.122
Silkworms p50T