Isolation and expression of cDNA coding for a new member of the phospholipase A2 inhibitor family.
The placental protein PP41,2 was shown to have thromboplastin-inhibitor activity. We used partial amino acid sequence information from PP4 cyanogen bromide fragments to design oligonucleotide probes for the screening of a human placental cDNA library. In addition to the PP4 cDNA we isolated a cDNA coding for a protein with considerable homology which we subsequently termed PP4-X. PP4 and PP4-X belong to the phospholipase A2 inhibitor family, as judged by their homology to lipocortin I and calpactin I3. The full-length PP4-X cDNA encodes a protein of 321 amino acid residues including a fourfold repeat structure. Northern blot analysis using the PP4-X cDNA reveals two hybridizing RNA species of approximately 1400 nucleotides and 2500 nucleotides, respectively. The shorter one could well represent the PP4-X transcript which is in good agreement with the isolated cDNA insert of 1326 nucleotides. Expression of the PP4-X coding sequence in E. coli resulted in the appearance of a protein which crossreacts with antibodies raised against PP4.
Grundmann
U
U
Research Laboratories of Behringwerke AG, Marburg, W.-Germany.
Amann
E
E
Abel
K J
KJ
Küpper
H A
HA
D017304:Annexin A5; D017302:Annexins; D001483:Base Sequence; D002135:Calcium-Binding Proteins / Q000235:genetics; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D010740:Phospholipases / Q000037:antagonists & inhibitors*; D010741:Phospholipases A / Q000037:antagonists & inhibitors*; D054467:Phospholipases A2; D011257:Pregnancy Proteins / Q000235:genetics
D017304:Annexin A5; D017302:Annexins; D002135:Calcium-Binding Proteins; D006023:Glycoproteins; D011257:Pregnancy Proteins; D004247:DNA; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2