Complete amino acid sequences and phosphorylation sites, determined by Edman degradation and mass spectrometry, of rat parotid destrin- and cofilin-like proteins.
Beta-adrenergic or cholinergic stimulation of the rat parotid gland was earlier shown to induce dephosphorylation of endogenous destrin- and cofilin-like proteins, which are phosphorylated in resting cells at Ser residues probably present near the N-terminals. The primary structures and phosphorylation sites were determined here. The rat destrin-like protein had a sequence 95% identical to the cDNA-derived sequence of porcine destrin. The rat cofilin-like protein was 98% identical to that of porcine cofilin. Each protein lacked the initiator Met and began with an acetylalanine residue followed by a Ser residue. The N-terminal peptides generated with endoproteinase Asp-N were isolated; they were each phosphorylated at Ser-2. Earlier work had shown that partial cleavage of the phosphorylated destrin- and cofilin-like proteins with cyanogen bromide provides unphosphorylated 16.7- and 18.3-kDa fragments, respectively. It was here confirmed that they contained all the Ser residues other than those present in the N-terminal peptides. From these observations, it was now concluded that the destrin- and cofilin-like proteins are rat parotid destrin and cofilin (non-muscle type), respectively, and that each protein is phosphorylated exclusively at Ser-2 in resting cells and dephosphorylated at this site in response to beta-adrenergic or cholinergic stimulation.
Kanamori
T
T
Department of Biochemistry, School of Dentistry, Aichi-Gakuin University, Nagoya, Japan.
Suzuki
M
M
Titani
K
K
D051339:Actin Depolymerizing Factors; D000409:Alanine / Q000031:analogs & derivatives / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics*; D003488:Cyanogen Bromide; D003598:Cytoskeletal Proteins; D018076:DNA, Complementary; D051345:Destrin; D010450:Endopeptidases / Q000235:genetics; D008297:Male; D013058:Mass Spectrometry; D008666:Metalloendopeptidases; D008715:Methionine / Q000235:genetics; D008840:Microfilament Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010306:Parotid Gland / Q000378:metabolism*; D010766:Phosphorylation; D051381:Rats; D017208:Rats, Wistar; D011943:Receptors, Adrenergic, beta / Q000378:metabolism; D011950:Receptors, Cholinergic / Q000378:metabolism; D012471:Salivary Proteins and Peptides / Q000235:genetics*; D012694:Serine / Q000235:genetics; D013552:Swine
D051339:Actin Depolymerizing Factors; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D018076:DNA, Complementary; D051345:Destrin; D008840:Microfilament Proteins; D011943:Receptors, Adrenergic, beta; D011950:Receptors, Cholinergic; D012471:Salivary Proteins and Peptides; C010530:N-acetylalanine; D012694:Serine; D008715:Methionine; D010450:Endopeptidases; D008666:Metalloendopeptidases; C058921:endoproteinase Asp-N; D000409:Alanine; D003488:Cyanogen Bromide