Abstract:
:Schistosoma mansoni leucine aminopeptidase (LAP) is thought to play a central role in hatching of the miracidium from the schistosome egg. We identified two discrete LAPs genes in the S. mansoni genome, and their orthologs in S. japonicum. The similarities in sequence and exon/intron structure of the two genes, LAP1 and LAP2, suggest that they arose by gene duplication and that this occurred before separation of the mansoni and japonicum lineages. The SmLAP1 and SmLAP2 genes have different expression patterns in diverse stages of the cycle; whereas both are equally expressed in the blood dwelling stages (schistosomules and adult), SmLAP2 expression was higher in free living larval (miracidia) and in parasitic intra-snail (sporocysts) stages. We investigated the role of each enzyme in hatching of schistosome eggs and the early stages of schistosome development by RNA interference (RNAi). Using RNAi, we observed marked and specific reduction of mRNAs, along with a loss of exopeptidase activity in soluble parasite extracts against the diagnostic substrate l-leucine-7-amido-4-methylcoumarin hydroxide. Strikingly, knockdown of either SmLAP1 or SmLAP2, or both together, was accompanied by >or=80% inhibition of hatching of schistosome eggs showing that both enzymes are important to the escape of miracidia from the egg. The methods employed here refine the utility of RNAi for functional genomics studies in helminth parasites and confirm these can be used to identify potential drug targets, in this case schistosome aminopeptidases.
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
Rinaldi G,Morales ME,Alrefaei YN,Cancela M,Castillo E,Dalton JP,Tort JF,Brindley PJdoi
10.1016/j.molbiopara.2009.05.002subject
Has Abstractpub_date
2009-10-01 00:00:00pages
118-26issue
2eissn
0166-6851issn
1872-9428pii
S0166-6851(09)00141-8journal_volume
167pub_type
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pub_type: 杂志文章,评审
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journal_title:Molecular and biochemical parasitology
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journal_title:Molecular and biochemical parasitology
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:2002-01-01 00:00:00
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更新日期:2002-03-01 00:00:00