title: Primary structure of bovine calpactin I heavy chain (p36), a major cellular substrate for retroviral protein-tyrosine kinases: homology with the human phospholipase A2 inhibitor lipocortin.
abstract: An amplified Okayama-Berg plasmid cDNA library was constructed from total poly(A)+ RNA isolated from the Madin-Darby bovine kidney cell line MDBK. This library was screened with a partial murine calpactin I heavy chain (p36) cDNA clone, the identification of which was based on bovine p36 tryptic peptide sequences generated during the course of these studies. The largest p36 cDNA insert (p36/6 of 1.6 kilobase pairs) was fully sequenced by the dideoxy method. The DNA sequence of this insert had an open reading frame of 1014 base pairs and coded for a protein with a molecular weight of 38 481. The deduced protein sequence of 338 residues was concordant with 173 residue positions of p36 determined at the protein level. The 5'- and 3'-ends of p36/6 contained 54 and 307 base pairs of untranslated sequence, respectively. Examination of poly(A)+ RNA prepared from the Madin-Darby cell line indicated a p36 mRNA species of about 1.6 kilobases. Four regions of internal homology, each about 70 amino acid residues in length, were observed in the deduced protein sequence for p36. Thirty-three of the 70 residue positions were conserved in at least three of the four repeating units. A comparison of derived amino acid sequence for bovine p36 with that previously determined for human lipocortin [Wallner, B. P., Mattaliano, R. J., Hession, C., Cate, R. L., Tizard, R., Sinclair, L. K., Foeller, C., Chow, E. P., Browning, J. L., Ramachandran, K. L., & Pepinsky, R. B. (1986) Nature (London) 320, 77-81] revealed extensive homology (66% overall) and the presence of four repetitive regions in the lipocortin structure.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017302:Annexins; D001483:Base Sequence; D002135:Calcium-Binding Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D002417:Cattle; D002460:Cell Line; D004247:DNA / Q000378:metabolism; D006023:Glycoproteins / Q000235:genetics*; D006801:Humans; D046911:Macromolecular Substances; D010446:Peptide Fragments / Q000032:analysis; D010741:Phospholipases A / Q000037:antagonists & inhibitors; D054467:Phospholipases A2; D010957:Plasmids; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D012689:Sequence Homology, Nucleic Acid; D014357:Trypsin
chemical_list: D017302:Annexins; D002135:Calcium-Binding Proteins; D006023:Glycoproteins; D046911:Macromolecular Substances; D010446:Peptide Fragments; D004247:DNA; D011505:Protein-Tyrosine Kinases; D010741:Phospholipases A; D054467:Phospholipases A2; D014357:Trypsin