Melatonin synthesis:: arylalkylamine N-acetyltransferases in trout retina and pineal organ are different

被引：48

作者：

Benyassi, A

Schwartz, C

Coon, SL

Klein, DC

Falcón, J ^{[1
]}

机构：

[1] NICHHD, Sect Neuroendocrinol, Dev Neurobiol Lab, NIH, Bethesda, MD 20892 USA

[2] Univ Poitiers, CNRS, UMR 6558, Lab Neurobiol Cellulaire & Neuroendocrinol, F-86022 Poitiers, France

[3] Fac Sci Fes, Physiol Anim Lab, Fes, Morocco

来源：

NEUROREPORT | 2000年 / 11卷 / 02期

关键词：

arylalkylamine N-acetyltransferase; fish; pineal organ; retina;

D O I：

10.1097/00001756-200002070-00006

中图分类号：

Q189 [神经科学];

学科分类号：

071006 ;

摘要：

Serotonin N-acetyltransferase (AANAT) is the first enzyme in the conversion of serotonin to melatonin. Changes in AANAT activity determine the daily rhythm in melatonin secretion. Two AANAT genes have been identified in the pike, pAANAT-1 and pAANAT-2, expressed in the retina and in the pineal, respectively. The genes preferentially expressed in these tissues encode proteins with distinctly different kinetic characteristics. Like the pike, trout retina primarily expresses the AANAT-1 gene and trout pineal primarily expresses the AANAT-2 gene. Here we show that the kinetic characteristics of AANAT in these tissues differ as in pike. These differences include optimal temperature for activity (pineal: 12 degrees C; retina: 25 degrees C) and relative affinity for indoleethylamines compared to phenylethylamines. In addition, retinal AANAT exhibited substrate inhibition, which was not seen with pineal AANAT. The kinetic differences between AANAT-1 and AANAT-2 appear to be defining characteristics of these gene subfamilies, and are not species specific. NeuroReport 11:255-258 (C) 2000 Lippincott Williams & Wilkins.

引用

页码：255 / 258

页数：4

共 9 条

[1] Transcripts encoding two melatonin synthesis enzymes in the teleost pineal organ:: Circadian regulation in pike and Zebrafish, but not in trout [J].