Modular changes of cis-regulatory elements from two functional pit1 genes in the duplicated genome of Cyprinus carpio

Kausel G.; Salazar M.; Castro L.; Vera T.; Romero A.; Muller, M.; Figueroa J.

Abstract

The pituitary-specific transcription factor Pit1 is involved in its own regulation and in a network of transcriptional regulation of hypothalamo-hypophyseal factors including prolactin (PRL) and growth hormone (CH). In the ectotherm teleost Cyprinus carpio. Pit1 plays an important role in regulation of the adaptive response to seasonal environmental changes. Two Pit1 genes exist in carp, a tetraploid vertebrate and transcripts of both genes were detected by RT-PCR analysis. Powerful comparative analyses of the 5′-flanking regions revealed copy specific changes comprising modular functional units in the naturally evolved promoters. These include the precise replacement of four nucleotides around the transcription start site embedded in completely conserved regions extending upstream of the TATA-box, an additional transcription factor binding site in the 5′-UTR of gene-I and, instead, duplication of a 9 bp element in gene-II. Binding of nuclear factors was assessed by electro mobility shift assays using extracts from rat pituitary cells and carp pituitary. Binding was confirmed at one conserved Pit1, one conserved CREB and one consensus MTF1. Interestingly, two functional Pit1 sites and one putative MTF1 binding site are unique to the Pit1 gene-I. In situ hybridization experiments revealed that the expression of gene-I in winter carp was significantly stronger than that of gene-II. Our data suggest that the specific control elements identified in the proximal regulatory region are physiologically relevant for the function of the duplicated Pit1 genes in carp and highlight modular changes in the architecture of two Pit1 genes that evolved for at least 12 MYA in the same organism. © 2006 Wiley-Liss, Inc.

Más información

Título según WOS: Modular changes of cis-regulatory elements from two functional pit1 genes in the duplicated genome of Cyprinus carpio
Título según SCOPUS: Modular changes of cis-regulatory elements from two functional Pit1 genes in the duplicated genome of Cyprinus carpio
Título de la Revista: JOURNAL OF CELLULAR BIOCHEMISTRY
Volumen: 99
Número: 3
Editorial: WILEY-BLACKWELL
Fecha de publicación: 2006
Página de inicio: 905
Página final: 921
Idioma: English
URL: http://doi.wiley.com/10.1002/jcb.20987
DOI:

10.1002/jcb.20987

Notas: ISI, SCOPUS