A pineal regulatory element (PIRE) mediates transactivation by the pineal/retina-specific transcription factor CRX

AUTOR(ES)

Li, Xiaodong

FONTE

The National Academy of Sciences

RESUMO

The circadian hormone melatonin is synthesized predominantly in the pineal gland by the actions of two pineal-specific enzymes: serotonin N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT). Pineal night-specific ATPase (PINA), another pineal- and night-specific protein we recently identified, is produced as a truncated form of the Wilson disease gene (Atp7b) product. To identify the regulatory elements required for pineal-specific gene expression, we isolated sequences upstream of the rat PINA gene and discovered a cis-acting element that is recognized by a novel pineal/retina-specific nuclear factor. This pineal regulatory element (PIRE) has a consensus of TAATC/T and is present in six copies in the 5′ regulatory region of the PINA gene, at least three copies in the rat NAT promoter, and at least one copy in each of the putative HIOMT promoters A and B. A recently identified retina-specific protein, cone rod homeobox (CRX), binds to PIRE in vitro and transactivates PIRE-reporter constructs. These data suggest that Crx may play a crucial role in regulating pineal gene expression through interactions with PIRE.

Documentos Relacionados

• Induction by interleukin-6 of interferon regulatory factor 1 (IRF-1) gene expression through the palindromic interferon response element pIRE and cell type-dependent control of IRF-1 binding to DNA.
• Modulation of CRX Transactivation Activity by Phosducin Isoforms†
• Interferon regulatory factor 1 (IRF-1) mediates cell growth inhibition by transactivation of downstream target genes.
• Pineal expression-promoting element (PIPE), a cis-acting element, directs pineal-specific gene expression in zebrafish
• A regulatory element is characterized by purine-mediated and cell-type-specific gene transcription.