Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
48
pubmed:dateCreated
2007-11-27
pubmed:databankReference
pubmed:abstractText
Diapause-specific peptide (DSP), derived from the leaf beetle, inhibits Ca2+ channels and has antifungal activity. DSP acts on chromaffin cells of the adrenal medulla in a fashion similar to that of omega-conotoxin GVIA, a well-known neurotoxic peptide, and blocks N-type voltage-dependent Ca2+ channels. However, the amino acid sequence of DSP has little homology with any other known Ca2+ channel blockers or antifungal peptides. In this paper, we analyzed the solution structure of DSP by using two-dimensional 1H nuclear magnetic resonance and determined the pairing of half-cystine residues forming disulfide bonds. The arrangement of the three disulfide bridges in DSP was distinct from that of other antifungal peptides and conotoxins. The overall structure of DSP is compact due in part to the three disulfide bridges and, interestingly, is very similar to those of the insect- and plant-derived antifungal peptides. On the other hand, the disulfide arrangement and the three-dimensional structure of DSP and GVIA are not similar. Nevertheless, some surface residues of DSP superimpose on the key functional residues of GVIA. This homologous distribution of hydrophobic and charged side chains may result in the functional similarity between DSP and GVIA. Thus, we propose here that the three-dimensional structure of DSP can explain its dual function as a Ca2+ channel blocker and antifungal peptide.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
4
pubmed:volume
46
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13733-41
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
The structure of a novel insect peptide explains its Ca2+ channel blocking and antifungal activities.
pubmed:affiliation
Faculty of Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't