Cloning of the proteinase that facilitates infection by schistosome parasites

• Published in: The Journal of biological chemistry Vol. 263; no. 26; pp. 13179 - 13184
• Main Authors: Newport, G R, McKerrow, J H, Hedstrom, R, Petitt, M, McGarrigle, L, Barr, P J, Agabian, N
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 15.09.1988; American Society for Biochemistry and Molecular Biology
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Biological and medical sciences; Biotechnology; Cloning, Molecular; DNA - analysis; Fundamental and applied biological sciences. Psychology; Gene expression; Genetic engineering; Genetic technics; Methods. Procedures. Technologies; Molecular and cellular biology; Molecular cloning; Molecular genetics; Molecular Sequence Data; Nucleic Acid Hybridization; Pancreatic Elastase - analysis; Pancreatic Elastase - genetics; Schistosoma mansoni; Schistosoma mansoni - enzymology; Schistosomiasis - enzymology; Schistosomiasis - transmission; Serine Endopeptidases - genetics; Molecular hybridization; Schistosoma mansoni; Transcription; Enzyme; Proteinase; Plathelmintha; Trematod disease; Gene expression; Helminthiasis; Trematoda; Infection; Posttranslational modification; Schistosomiasis; Regulation(control); Complementary DNA; Helmintha; Invertebrata; Molecular cloning; Sporocyst
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)37688-9

Four cDNA clones encoding a proteinase which facilitates skin invasion by schistosome parasites were isolated by screening a schistosome sporocyst cDNA library, using an oligonucleotide probe containing sequences complementary to predicted 5′-translated regions of its RNA. The amino acid sequence of the enzyme, as deduced from the DNA sequence of the clones, indicates that the enzyme is a serine protease which in many respects is similar to vertebrate pancreatic elastases, although regions outside of the putative active site, binding pocket, and amino-terminal cysteines differ significantly. Regulation of expression of the enzyme occurs at the level of mRNA transcription as well as posttranslationally, the latter involving the processing of a previously unidentified pre-proenzyme (zymogen) sequence. In situ hybridization of the cDNA clones to tissue sections of developing larvae indicates that the enzyme is synthesized within a discrete time frame in specialized cells of the organism.