Structure of cDNA coding for rat platelet phospholipase A2.
Three cDNA clones coding for rat platelet phospholipase A2 and a homologous protein were isolated from a rat megakaryocyte cDNA library and sequenced. One (prPLA2-1) carries a 708 nucleotide long insert. The others (prPLA2-2 and -3) differ from clone 1 in three nucleotides and have a 748 nucleotide long insert. All contain a single open reading frame which encodes a 146 amino acid long polypeptide. Based on the deduced amino acid sequence, we concluded that prPLA2-1 encodes rat platelet phospholipase A2. prPLA2-2 and -3 most probably encode a protein homologous to phospholipase A2 with two amino acid replacements. A typical signal peptide sequence (21 amino acid long), located at the NH2 termini of the deduced structure, was immediately followed by a polypeptide which corresponds to the mature enzyme, suggesting that the rat platelet enzyme is not expressed as a proenzyme form. Northern blot analysis showed a single transcript, which is 900 to 1,100 nucleotides long, in the poly(A)+RNA fractions of rat megakaryocytes, bone marrow cells, peritoneal cells of caseinate-treated rats, and spleen cells.
Komada
M
M
Faculty of Pharmaceutical Sciences, University of Tokyo.
Kudo
I
I
Mizushima
H
H
Kitamura
N
N
Inoue
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001792:Blood Platelets / Q000201:enzymology*; D015152:Blotting, Northern; D004247:DNA / Q000235:genetics*; D008969:Molecular Sequence Data; D010740:Phospholipases / Q000235:genetics*; D010741:Phospholipases A / Q000235:genetics*; D054467:Phospholipases A2; D051381:Rats
D004247:DNA; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2