title: Specificity of the sex-influenced esterase (ES-SI) isozyme in rat liver.
abstract: A carboxylesterase which shares common antigenicity with sex-influenced esterase (ES-SI) was found in both the male and the female liver of the rat but not in the following tissues: erythrocyte, heart, kidney, lung, spleen, small intestine, testis, thymus, and lymph node. Subcellular fractionation showed the esterase localizes in the microsome-rich fraction. The strain distribution of the presence or absence of the esterase in inbred rats was identical to that of ES-SI, although in adult males a considerable amount of the esterase exists, unlike ES-SI. The esterase had a higher isoelectric point than ES-SI but after neuraminidase treatment the difference disappeared, suggesting that the esterase has a sialic acid moiety. Because this esterase has different properties from those previously reported, it is proposed that it is designated liver-ES-SI. The common antigenicity and similar strain distribution between ES-SI and liver-ES-SI suggest that liver-ES-SI is a precursor molecule of ES-SI and therefore the two esterases are products of a single gene.
authors.affiliation: Institute for Experimental Animals, School of Medicine, Kanazawa University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Nikaido
authors.forename: T
authors.initials: T
authors.lastname: Hirose
authors.forename: O
authors.initials: O
authors.lastname: Nikaido
authors.forename: J
authors.initials: J
authors.lastname: Yamada
authors.forename: J
authors.initials: J
authors.lastname: Hayakawa
mesh_terms: D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000097:blood / Q000737:chemistry / Q000378:metabolism*; D004792:Enzyme Precursors / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D007525:Isoelectric Focusing; D007527:Isoenzymes / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology; D011110:Polymorphism, Genetic; D051381:Rats; D011919:Rats, Inbred Strains; D012737:Sex Factors; D013045:Species Specificity; D013379:Substrate Specificity; D014018:Tissue Distribution
chemical_list: D004792:Enzyme Precursors; D007527:Isoenzymes; D002265:Carboxylic Ester Hydrolases; C072428:sex-influenced esterase