Cellular stabilization of the melatonin rhythm enzyme induced by nonhydrolyzable phosphonate incorporation

• Published in: Nature structural & molecular biology Vol. 10; no. 12; pp. 1054 - 1057
• Main Authors: Cole, Philip A, Zheng, Weiping, Zhang, Zhongsen, Ganguly, Surajit, Weller, Joan L, Klein, David C
• Format: Journal Article
• Language: English
• Published: United States Nature Publishing Group 01.12.2003
• Subjects: Amino Acid Sequence; Animals; Arylamine N-Acetyltransferase - chemical synthesis; Arylamine N-Acetyltransferase - chemistry; Arylamine N-Acetyltransferase - metabolism; CHO Cells; Circadian Rhythm; Cricetinae; Melatonin - metabolism; Molecular Sequence Data; Peptide Fragments - chemistry; Recombinant Proteins - chemistry; Recombinant Proteins - metabolism; Transfection
• ISSN: 1072-8368; 1545-9993; 2331-365X; 1545-9985
• DOI: 10.1038/nsb1005

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.