Sequence of sites on ATP-citrate lyase and phosphatase inhibitor 2 phosphorylated by multifunctional protein kinase (a glycogen synthase kinase 3 like kinase).
Multifunctional protein kinase (MFPK) phosphorylates ATP-citrate lyase on peptide B on two sites, BT and BS, on threonine and serine, respectively, inhibitor 2 on a threonyl residue, and glycogen synthase at sites 2 and 3. The phosphorylation sites BT and BS of ATP-citrate lyase are dependent on prior phosphorylation at site A whereas site A phosphorylation is decreased by prior phosphorylation at sites BT and BS. To study the MFPK recognition sites and the site-site interactions, the amino acid sequences of ATP-citrate lyase peptide B and inhibitor 2 were determined and compared to each other and to glycogen synthase sites 3-5. The sequence of the tryptic peptide containing the two phosphorylation sites of peptide B is -Phe-Leu-Leu-Asn-Ala-Ser-Gly-Ser-Thr-Ser-Thr(P)-Pro-Ala-Pro-Ser(P)-Arg-, and the sequence of the MFPK phosphorylation site of inhibitor 2 is -Ile-Asp-Glu-Pro-Ser-Thr(P)-Pro-Tyr-. This inhibitor 2 site is identical with the site phosphorylated by glycogen synthase kinase 3/FA. These results suggest that at least some of the sites phosphorylated by MFPK (BT of ATP-citrate lyase, Thr 72 of inhibitor 2, and sites 3b and 4 of glycogen synthase) contain a Ser/Thr flanked by a carboxyl-terminal proline. However, as MFPK did not phosphorylate a series of peptides containing the -X-Thr/Ser-Pro-X- sequence, this minimum consensus sequence is not sufficient for phosphorylation by MFPK.(ABSTRACT TRUNCATED AT 250 WORDS)
Ramakrishna
S
S
Department of Physiology and Biophysics, School of Medicine, State University of New York, Stony Brook 11794.
D'Angelo
G
G
Benjamin
W B
WB
D001275:ATP Citrate (pro-S)-Lyase / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D038341:Glycogen Synthase Kinases; D008969:Molecular Sequence Data; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D011506:Proteins / Q000494:pharmacology*; D051381:Rats; D013379:Substrate Specificity / Q000187:drug effects; D000097847:Protein Phosphatase Inhibitory Proteins
D001275:ATP Citrate (pro-S)-Lyase; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D038341:Glycogen Synthase Kinases; D010749:Phosphoprotein Phosphatases; D011494:Protein Kinases; D011506:Proteins; C024833:protein phosphatase inhibitor-2; D000097847:Protein Phosphatase Inhibitory Proteins