High impact information on Spink3

• Reduction and alkylation of cysteine residues suppressed the immunologic response of mouse caltrin; however, modified rat caltrin retained partially its immunoreactivity with the antiserum against guinea pig caltrin I [1].
• Reduction and carboxymethylation of the cysteine residues abolished the inhibitor activity of both caltrin proteins [2].
• Dramatic inhibition of trypsin activity by rat caltrin and guinea pig caltrin I was spectrophotometrically demonstrated using the artificial substrate benzoylarginyl ethyl ester [2].
• Isolation and characterization of a 54-kilodalton precursor of caltrin, the calcium transport inhibitor protein from seminal vesicles of the rat [3].
• Its complete amino acid sequence was identical with that of pancreatic secretory trypsin inhibitor II (PSTI-II) in pancreatic juice, but not with that of PSTI-I [Uda, K., Ogawa, M., Shibata, T., Murata, A., Mori, T., Kikuchi, N., Yoshida, N., Tsunasawa, S. & Sakiyama, F. (1988) Biol. Chem. Hoppe-Seyler 369, 55-61] [4].

Biological context of Spink3

• Both predicted amino acid sequences consisting of 79 amino acids, with the secretion signal peptide consisting of 18 and 23 amino acids for PSTI-I and PSTI-II, respectively [5].
• Southern blot analyses suggested that both PSTI-I and PSTI-II genes are single copy genes per haploid genome [5].
• Respiration studies demonstrate a marked stimulation of oxygen consumption by caltrin in filipin-treated spermatozoa and rat liver mitochondria [6].

Anatomical context of Spink3

• Here we report for the first time that PSTI-II is present in other normal tissues besides the pancreas [4].
• Inhibition by caltrin of calcium transport into spermatozoa, liver and heart mitochondria [6].
• Only a marginal effect of caltrin on respiration of intact spermatozoa was observed; indicating that the plasma membrane is impermeable to this protein [6].
• The calcium-transport inhibitor, caltrin, isolated from bovine seminal fluid inhibits calcium accumulation by bovine epididymal spermatozoa, spermatozoal mitochondria, rat liver mitochondria and beef heart mitochondria [6].
• No caltrin immunoreaction was detected 14 days postcastration, and the ultrastructure of the epithelial cells was markedly altered [7].

Associations of Spink3 with chemical compounds

• Androgen-dependent synthesis/secretion of caltrin, calcium transport inhibitor protein of mammalian seminal vesicle [7].
• Data suggest that the synthesis and secretion of caltrin are testosterone-dependent processes [7].

Other interactions of Spink3

• Northern blot analyses showed that PSTI-I is expressed in the pancreas, whereas PSTI-II is expressed in the pancreas and the liver using the same promoter [5].
• SDS-PAGE and Western blotting of the seminal vesicle secretion revealed alterations in the protein pattern and loss of the caltrin-related immunoreactive bands [7].

Analytical, diagnostic and therapeutic context of Spink3

• Effects of androgen status on the synthesis and secretion of rat caltrin have been studied by three different procedures: a) immunocytochemistry in seminal vesicle tissues; b) polyacrylamide gel electrophoresis and Western immunostaining of seminal vesicle secretion; and c) evaluation of trypsin inhibitory activity of the seminal vesicle secretion [7].

References