TY - JOUR
T1 - Hypoxia-Inducible Factor α and Hif-prolyl Hydroxylase Characterization and Gene Expression in Short-Time Air-Exposed Mytilus galloprovincialis
AU - Giannetto, Alessia
AU - Maisano, Maria
AU - Cappello, Tiziana
AU - Oliva, Sabrina
AU - Parrino, Vincenzo
AU - Natalotto, Antonino
AU - De Marco, Giuseppe
AU - Barberi, Chiara
AU - Romeo, Orazio
AU - Mauceri, Angela
AU - Fasulo, Salvatore
PY - 2015/8/16
Y1 - 2015/8/16
N2 - Aquatic organisms experience environmental hypoxia as a result of eutrophication and naturally occurring tidal cycles. Mytilus galloprovincialis, being an anoxic/hypoxic-tolerant bivalve, provides an excellent model to investigate the molecular mechanisms regulating oxygen sensing. Across the animal kingdom, inadequacy in oxygen supply is signalled predominantly by hypoxia-inducible factors (HIF) and Hif-prolyl hydroxylases (PHD). In this study, hif-α 5′-end and partial phd mRNA sequences from M. galloprovincialis were obtained. Phylogenetic and molecular characterization of both HIF-α and PHD putative proteins showed shared key features with the respective orthologues from animals strongly suggesting their crucial involvement in the highly conserved oxygen sensing pathway. Both transcripts displayed a tissue-specific distribution with prominent expression in gills. Quantitative gene expression analysis of hif-α and phd mRNAs from gills of M. galloprovincialis demonstrated that both these key sensors are transcriptionally modulated by oxygen availability during the short-time air exposure and subsequent re-oxygenation treatments proving that they are critical players of oxygen-sensing mechanisms in mussels. Remarkably, hif-α gene expression showed a prompt and transient response suggesting the precocious implication of this transcription factor in the early phase of the adaptive response to hypoxia in Mytilus. HIF-α and PHD proteins were modulated in a time-dependent manner with trends comparable to mRNA expression patterns, thus suggesting a central role of their transcriptional regulation in the hypoxia tolerance strategies in marine bivalves. These results provide molecular information about the effects of oxygen deficiency and identify hypoxia-responsive biomarker genes in mussels applicable in ecotoxicological studies of natural marine areas.
AB - Aquatic organisms experience environmental hypoxia as a result of eutrophication and naturally occurring tidal cycles. Mytilus galloprovincialis, being an anoxic/hypoxic-tolerant bivalve, provides an excellent model to investigate the molecular mechanisms regulating oxygen sensing. Across the animal kingdom, inadequacy in oxygen supply is signalled predominantly by hypoxia-inducible factors (HIF) and Hif-prolyl hydroxylases (PHD). In this study, hif-α 5′-end and partial phd mRNA sequences from M. galloprovincialis were obtained. Phylogenetic and molecular characterization of both HIF-α and PHD putative proteins showed shared key features with the respective orthologues from animals strongly suggesting their crucial involvement in the highly conserved oxygen sensing pathway. Both transcripts displayed a tissue-specific distribution with prominent expression in gills. Quantitative gene expression analysis of hif-α and phd mRNAs from gills of M. galloprovincialis demonstrated that both these key sensors are transcriptionally modulated by oxygen availability during the short-time air exposure and subsequent re-oxygenation treatments proving that they are critical players of oxygen-sensing mechanisms in mussels. Remarkably, hif-α gene expression showed a prompt and transient response suggesting the precocious implication of this transcription factor in the early phase of the adaptive response to hypoxia in Mytilus. HIF-α and PHD proteins were modulated in a time-dependent manner with trends comparable to mRNA expression patterns, thus suggesting a central role of their transcriptional regulation in the hypoxia tolerance strategies in marine bivalves. These results provide molecular information about the effects of oxygen deficiency and identify hypoxia-responsive biomarker genes in mussels applicable in ecotoxicological studies of natural marine areas.
KW - Gene expression
KW - Hypoxia-inducible factor
KW - Mytilus galloprovincialis
KW - Oxygen sensing
UR - http://www.scopus.com/inward/record.url?scp=84946493737&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84946493737&partnerID=8YFLogxK
U2 - 10.1007/s10126-015-9655-7
DO - 10.1007/s10126-015-9655-7
M3 - Article
C2 - 26277612
AN - SCOPUS:84946493737
VL - 17
SP - 768
EP - 781
JO - Molecular Marine Biology and Biotechnology
JF - Molecular Marine Biology and Biotechnology
SN - 1436-2228
IS - 6
ER -