A novel transcript encoding a
cysteine-rich
granulin-like
peptide (l-grn) was identified in the hepatopancreas of the marine intertidal gastropod, Littorina littorea, an
anoxia-tolerant species. Experimental exposure of snails to
anoxia induced a gradual accumulation of l-grn transcripts over time, with expression regulated in vitro through elements responsive to second messengers of
protein kinases A, C and G. Translation of this transcript was analyzed by examining l-grn association with ribosomes during normoxia,
anoxia, and aerobic recovery. Transcripts of l-grn were associated with polysomes during normoxia, moved into the monosome fractions under
anoxia, but shifted back to the polysomal fractions during aerobic recovery. Western blotting confirmed this with a
granulin-like
protein detected under normoxic conditions, but not during
anoxia exposure. A significant increase in the precursor
protein and
peptide (L-GRN) was observed during the aerobic recovery period. The accumulation of l-grn transcripts during anoxic exposure and subsequent translation following the return to aerobic conditions may be a response to
oxidant damage that occurs during re-oxygenation. Overall, the data show that the l-grn gene is
anoxia-responsive in this species and may have pro-survival functions during the recovery period.