Characterization of a complementary deoxyribonucleic acid coding for human and bovine plasminogen

Abstract

A cDNA library was constructed in pBR322 from bovine liver mRNA that was enriched for plasminogen mRNA by polysome immunoprecipitation. A 32P-labeled single-stranded cDNA was then prepared from the enriched bovine mRNA and employed as a probe to screen the cDNA library. The screening was carried out by testing for clones that protect the hybridized 32P-labeled cDNA from S1 nuclease digestion. The longest clone that was found was 581 base pairs in length and coded for the C-terminal 107 amino acids of bovine plasminogen, a 3' noncoding region of 246 nucleotides and a poly(A) tail. The bovine cDNA clone was then used as a probe to screen a human liver cDNA library of 18 000 recombinants. Six isolates were found to contain human plasminogen sequences. The longest clone consisted of 1851 base pairs corresponding to amino acid residues 272-790, followed by a 3' noncoding region of 227 base pairs and a poly(A) tail. Restriction fragments of the human cDNA were then used as probes to screen a human genomic DNA library present in a Charon 4A lambda phage library. Approximately 50 isolates from 10(6) recombinants were identified that hybridized to varying degrees with the cDNA probe. Among these, 10 corresponding to the gene for human plasminogen have been analyzed, and 3 that overlap have been shown to extend from kringle 3 through the 3' noncoding region of the gene. A 160 base pair exon with flanking splice junctions was then characterized and shown to encode for the first half of plasminogen kringle 4, including amino acid residues 346-399.

Cloning and characterization of complementary DNA for human tryptase.

“…The amino acid sequence of the catalytic portion of tryptase exhibits a high degree of homology with the catalytic portions of thirteen other members of the trypsin superfamily of serine proteases (20, [33][34][35][36][37][38][39][40][41][42][43] (Fig. 3).…”

Molecular basis of apolipoprotein (a) isoform size heterogeneity as revealed by pulsed-field gel electrophoresis.

“…The apo(a) protein resembles plasminogen, the plasma zymogen for plasmin (17). The apo(a) and plasminogen cDNAs have been cloned (18)(19)(20) and the two genes are closely linked on chromosome 6 (q26-27) (21-25). The two cDNA sequences are remarkably similar (18).…”

The influence of the nature of the asparagine 289-linked oligosaccharide on the activation by urokinase and lysine binding properties of natural and recombinant human plasminogens.

“…92:249-254.) Key words: cell-specific glycosylation * plasminogen glycoforms * insect cell expressed human plasminogen * plasminogen activation* plasminogen/ ligand interactions Human plasminogen (HPg),' the zymogen form of the serine protease, HPm, is a circulating glycoprotein containing 791 amino acids in a single polypeptide chain (1)(2)(3)(4)(5) ). Activation of HPg occurs consequent to cleavage ofthe Arg56 l-Val562 peptide bond in the zymogen and results in formation of the twochain, disulfide-bond-stabilized, HPm.…”