Accumulation and translation of ferritin heavy chain transcripts following anoxia exposure in a marine invertebrate.
Differential screening of a Littorina littorea (the common periwinkle) cDNA library identified ferritin heavy chain as an anoxia-induced gene in hepatopancreas. Northern blots showed that ferritin heavy chain transcript levels were elevated twofold during anoxia exposure, although nuclear run-off assays demonstrated that ferritin heavy chain mRNAs were not transcriptionally upregulated during anoxia. Polysome analysis indicated that existing ferritin transcripts were actively translated during the anoxic period. This result was confirmed via western blotting, which demonstrated a twofold increase in ferritin heavy chain protein levels during anoxia, with a subsequent decrease to control levels during normoxic recovery. Organ culture experiments using hepatopancreas slices demonstrated a >50% increase in ferritin heavy chain transcript levels in vitro under conditions of anoxia and freezing, as well as after incubation with the second messenger cGMP. Taken together, these results suggest that ferritin heavy chain is actively regulated during anoxia exposure in the marine snail, L. littorea.
Larade
Kevin
K
Institute of Biochemistry and Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada, K1S 5B6.
Storey
Kenneth B
KB
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D006152:Cyclic GMP / Q000502:physiology*; D018076:DNA, Complementary / Q000235:genetics; D005293:Ferritins / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation; D043143:Hepatopancreas / Q000378:metabolism*; D000860:Hypoxia / Q000235:genetics*; D008969:Molecular Sequence Data; D011132:Polyribosomes / Q000235:genetics; D014176:Protein Biosynthesis; D015290:Second Messenger Systems / Q000502:physiology*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012908:Snails / Q000235:genetics* / Q000502:physiology; D013053:Spectrophotometry
D018076:DNA, Complementary; D005293:Ferritins; D006152:Cyclic GMP