Cloning of hif-1a and hif-2a and mRNA expression pattern during development in zebrafish.

ROJAS D.A.; MUNIZAGA D.A,; CENTANIN L.,; ANTONELLI M.,; WAPPNER P.,; ALLENDE M.L.; REYES A.E.

Gene expression patterns

Año: 2007 vol. 7 p. 339 - 345

1567-133X

Hypoxia-inducible factors (HIFs) regulate gene expression in response to hypoxia and in vertebrates they are known to participate in several developmental processes, including angiogenesis, vasculogenesis, heart and central nervous system development. Over the last decade,major progress in unraveling the molecular mechanisms that mediate regulation of HIF proteins by oxygen tension has been reported, but ourknowledge on their developmental regulation during embryogenesis in model organisms is limited. Expression of hif-1_ and hif-2_ genes hasbeen characterized during normal mouse development and they were found to be expressed from stages E7.5, later in E9.5 and E15.5 in severaldiVerent tissues such as the brain, heart and blood vessels. However, there is no detailed temporal information on their expression at otherembryonic stages, even though orthologous genes have been described in several diVerent vertebrate species. In this study, we describe the cloningand detailed expression pattern of zebraWsh hif-1_ and hif-2_ genes. Sequence analysis revealed that zebraWsh Hif proteins are highlyhomologous to other vertebrate orthologues. ZebraWsh hif-1_ and hif-2_ are both expressed throughout development in discrete territories in adynamic pattern. Interestingly, in the notochord the expression of hif-1_ is switched oV, while hif-2_ transcription is turned on, signifying thatthe two genes might have partially overlapping, although non-redundant functions in development. This is the Wrst time that a detailed comparisonof the expression of hif-1_ and hif-2_ is directly assessed in a vertebrate model system throughout development.