Data/hora: 01/06/2024 02:24:07

Provedor de dados: 	56	
País: 	Brazil	
Título: 	Modulation of rhodopsin gene expression and signaling mechanisms evoked by endothelins in goldfish and murine pigment cell lines	
Autores: 	Lopes,G.J.D.; Góis,C.C.; Lima,L.H.R.G.; Castrucci,A.M.L.	
Data: 	2010-09-01	
Ano: 	2010	
Palavras-chave: 	Rhodopsin; Sarafotoxin; Endothelin; Pigment cells; Gene expression; Signaling pathway.	
Resumo: 	Endothelins (ETs) and sarafotoxins (SRTXs) belong to a family of vasoconstrictor peptides, which regulate pigment migration and/or production in vertebrate pigment cells. The teleost Carassius auratus erythrophoroma cell line, GEM-81, and Mus musculus B16 melanocytes express rhodopsin, as well as the ET receptors, ETB and ETA, respectively. Both cell lines are photoresponsive, and respond to light with a decreased proliferation rate. For B16, the doubling time of cells kept in 14-h light (14L):10-h darkness (10D) was higher compared to 10L:14D, or to DD. The doubling time of cells kept in 10L:14D was also higher compared to DD. Using real-time PCR, we demonstrated that SRTX S6c (12-h treatment, 100 pM and 1 nM; 24-h treatment, 1 nM) and ET-1 (12-h treatment, 10 and 100 pM; 24- and 48-h treatments, 100 pM) increased rhodopsin mRNA levels in GEM-81 and B16 cells, respectively. This modulation involves protein kinase C (PKC) and the mitogen-activated protein kinase cascade in GEM-81 cells, and phospholipase C, Ca2+, calmodulin, a Ca2+/calmodulin-dependent kinase, and PKC in B16 cells. Cells were kept under constant darkness throughout the gene expression experiments. These results show that rhodopsin mRNA levels can be modulated by SRTXs/ETs in vertebrate pigment cells. It is possible that SRTX S6c binding to the ETB receptors in GEM-81 cells, and ET-1 binding to ETA receptors in B16 melanocytes, although activating diverse intracellular signaling mechanisms, mobilize transcription factors such as c-Fos, c-Jun, c-Myc, and neural retina leucine zipper protein. These activated transcription factors may be involved in the positive regulation of rhodopsin mRNA levels in these cell lines.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010000900004	
Editor: 	Associação Brasileira de Divulgação Científica	
Relação: 	10.1590/S0100-879X2010007500087	
Formato: 	text/html	
Fonte: 	Brazilian Journal of Medical and Biological Research  v.43 n.9 2010	
Fonte: 	info:eu-repo/semantics/openAccess