Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042961 (volvulus)
 4,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although the mechanisms underlying the host inflammatory response in ocular onchocerciasis have been examined, the role of particular parasite proteins in this process remains largely unexplored. Recently, it was found that one of the most abundant expressed sequence tags in Onchocerca volvulus infective larvae encoded a protein with similarities to a component of vespid venom. This clone was designated O. volvulus Activation associated Secreted Protein -1 (Ov-asp-1). We report the characterization of three members of a family of proteins, designated the Ov-ASP family, of which Ov-ASP-1 is a member. Sequence based and phylogenetic analyses suggest that these proteins form a filarial specific protein family related to both the vespid venom antigen 5 and the vertebrate CRISP/Tpx family of proteins. The three members of the Ov-ASP family exhibit distinct patterns of expression in the life cycle of O. volvulus. Genomic Southern blot analyses indicate that several genes encoding sequences related to the Ov-asp family are present in the genome of O. volvulus. Recombinant proteins expressed from full length cDNAs encoding two members of the Ov-asp family were found to induce an angiogenic response after injection into corneas of naive mice, and vessel formation was associated with only minor inflammatory cell infiltration. These data suggest that Ov-ASP proteins may directly induce an angiogenic response and may therefore contribute to corneal neovascularization in onchocercal keratitis.
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PMID:Angiogenic activity of Onchocerca volvulus recombinant proteins similar to vespid venom antigen 5. 1096 Jan 68

The Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) was one of the promising vaccine candidates against the most prevalent human hookworm species as adverse vaccine reaction has compromised further human vaccine trials. To elucidate the gene structure and the extent of sequence diversity, we determined the complete nucleotide sequence of the Na-asp-2 gene of individual larvae from 32 infected subjects living in 3 different endemic areas of Thailand. Sequence analysis revealed that the gene encoding Na-ASP-2 comprised 8 exons. Of 3 nucleotide substitutions in these exons, only one causes an amino acid change from leucine to methionine. A consensus conserved GT and AG at the 5' and the 3' boundaries of each intron was observed akin to those found in other eukaryotic genes. Introns of Na-asp-2 contained 23 nucleotide substitutions and 0-18 indels. The mean number of nucleotide substitutions per site (d) in introns was not significantly different from the mean number of synonymous substitutions per synonymous site (d(S)) in exons whereas d in introns was significantly exceeded d(N) (the mean number of nonsynonymous substitutions per nonsynonymous site) in exons (p<0.05), suggesting that introns and synonymous sites in exons may evolve at a similar rate whereas functional constraints at the amino acid could limit amino acid substitutions in Na-ASP-2. A recombination site was identified in an intron near the 3' portion of the gene. The positions of introns and the intron phases in the Na-asp-2 gene comparing with those in other pathogenesis-related-1 proteins of Loa loa, Onchocerca volvulus, Heterodera glycines, Caenorhabditis elegans and human were relatively conserved, suggesting evolutionary conservation of these genes. Sequence conservation in Na-ASP-2 may not compromise further vaccine design if adverse vaccine effects could be resolved whereas microheterogeneity in introns of this locus may be useful for population genetics analysis of N. americanus.
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PMID:Sequence conservation in the Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) from hookworm infected individuals in Thailand. 2296 44