Larade, K., and Storey, K.B. 2009. Living without oxygen: anoxia-responsive gene expression and regulation. Curr. Genomics 10, 76-85. DOI 10.1007/s11010-008-9959-2
Living
without Oxygen: Anoxia-Responsive Gene
Expression and Regulation
Kevin Larade and Kenneth B. Storey
Abstract
Many
species of marine mollusks demonstrate exceptional capacities for long term
survival without oxygen. Analysis of gene expression under anoxic conditions,
including the subsequent translational responses, allows examination of the
functional mechanisms that support and regulate natural anaerobiosis and permit
noninjurious transitions between aerobic and anoxic
states. Identification of stress-specific gene expression can provide
important insights into the metabolic adaptations that are needed for anoxia tolerance,
with potential applications to anoxia-intolerant systems. Various methods are
available to do this, including high throughput microarray screening and
construction and screening of cDNA libraries. Anoxia-responsive genes have been identified in mollusks; some have
known functions in other organisms but were not previously linked with anoxia
survival. In other cases, completely novel anoxia-responsive genes have been
discovered, some that show known motifs or domains that hint at function. Selected
genes are expressed at different times over an anoxia-recovery time course with
their transcription and translation being actively regulated to ensure protein
expression at the optimal time. An examination of transcript status over the
course of anoxia exposure and subsequent aerobic recovery identifies genes, and
the proteins that they encode, that enhance cell survival under oxygen-limited
conditions. Analysis of data generated from non-mainstream model systems allows
for insight into the response by cells to anoxia stress.