NeuroD1: developmental expression and eegulated genes in the rodent pineal gland

E. MUÑOZ; M. BAILEY; M. RATH; Q. SHI; F. MORIN; S. COON; M. MØLLER; D. KLEIN

JOURNAL OF NEUROCHEMISTRY

Año: 2007 vol. 102 p. 887 - 899

0022-3042

NeuroD1/BETA2, a member of the bHLH transcription factor family, is known to  influence  the  fate of  specific neuronal, endocrine and retinal cells. We report here that NeuroD1 mRNA is highly abundant in the developing and adult rat pineal gland.  Pineal expression begins in the 17-day embryo at which time it is also detectable in other brain regions.  Expression in the pineal gland increases during the embryonic period and is maintained thereafter at levels equivalent to those found in the cerebellum and retina. In contrast, NeuroD1 mRNA decreases markedly in non-cerebellar brain regions during development. Pineal NeuroD1 levels are similar during the day and night, and do not appear to be influenced by sympathetic neural input. Gene expression analysis of the pineal glands from neonatal NeuroD1 knockout mice identifies 127 transcripts that  are down-regulated  (>2-fold, p < 0.05) and 16 that are  up-regulated  (>2-fold, p < 0.05).  According to quantitative RT-PCR, the most dramatically down-regulated gene is kinesin family member 5C (~100-fold) and the most dramatically up-regulated gene is glutamic acid decarboxylase 1 (~4-fold).   Other impacted transcripts encode proteins involved in differentiation, development, signal transduction, and trafficking.   These findings represent the first step towards elucidating the role of NeuroD1 in the rodent pinealocyte.