Cellular stabilization of the melatonin rhythm enzyme induced by nonhydrolyzable phosphonate incorporation.
Serotonin N-acetyltransferase (arylalkylamine N-acetyltransferase, AANAT) controls daily changes in the production and circulating levels of melatonin. Here, the significance of the phosphorylation of AANAT was studied using a semisynthetic enzyme in which a nonhydrolyzable phosphoserine/threonine mimetic, phosphonomethylenealanine (Pma), was incorporated at position 31 (AANAT-Pma31). The results of studies in which AANAT-Pma31 and related analogs were injected into cells provide the first direct evidence that Thr31 phosphorylation controls AANAT stability in the context of the intact cells by binding to 14-3-3 protein. These findings establish Thr31 phosphorylation as an essential element in the intracellular regulation of melatonin production. The application of Pma in protein semisynthesis is likely to be broadly useful in the analysis of protein serine/threonine phosphorylation.
Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, Maryland 21205, USA.
Weiping
W
Zheng
Zhongsen
Z
Zhang
Surajit
S
Ganguly
Joan L
JL
Weller
David C
DC
Klein
Philip A
PA
Cole
D000595:Amino Acid Sequence; D000818:Animals; D001191:Arylamine N-Acetyltransferase / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism*; D016466:CHO Cells; D002940:Circadian Rhythm; D006224:Cricetinae; D008550:Melatonin / Q000378:metabolism*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D014162:Transfection
D010446:Peptide Fragments; D011994:Recombinant Proteins; D001191:Arylamine N-Acetyltransferase; D008550:Melatonin