Open AccessStructural and functional analysis of coral Hypoxia Inducible Factor
Author(s) -
Didier Zoccola,
Jonas Morain,
Gilles Pagès,
Natacha Caminiti-Segonds,
Sandy Giuliano,
Sylvie Tambutté,
Denis Allemand
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0186262
Subject(s) - stylophora pistillata , biology , coral , transcription factor , hypoxia (environmental) , microbiology and biotechnology , hypoxia inducible factors , anthozoa , in silico , gene , biochemistry , oxygen , chemistry , ecology , organic chemistry
Tissues of symbiotic Cnidarians are exposed to wide, rapid and daily variations of oxygen concentration. Indeed, during daytime, intracellular O 2 concentration increases due to symbiont photosynthesis, while during night, respiration of both host cells and symbionts leads to intra-tissue hypoxia. The Hypoxia Inducible Factor 1 (HIF-1) is a heterodimeric transcription factor used for maintenance of oxygen homeostasis and adaptation to hypoxia. Here, we carried out a mechanistic study of the response to variations of O 2 concentrations of the coral model Stylophora pistillata . In silico analysis showed that homologs of HIF-1 α (SpiHIF-1α) and HIF-1β (SpiHIF-1β) exist in coral. A specific SpiHIF-1 DNA binding on mammalian Hypoxia Response Element (HRE) sequences was shown in extracts from coral exposed to dark conditions. Then, we cloned the coral HIF-1α and β genes and determined their expression and transcriptional activity. Although HIF-1α has an incomplete Oxygen-dependent Degradation Domain (ODD) relative to its human homolog, its protein level is increased under hypoxia when tested in mammalian cells. Moreover, co-transfection of SpiHIF-1α and β in mammalian cells stimulated an artificial promoter containing HRE only in hypoxic conditions. This study shows the strong conservation of molecular mechanisms involved in adaptation to O 2 concentration between Cnidarians and Mammals whose ancestors diverged about 1,200–1,500 million years ago.