Analysis of
signal transduction pathways during anoxia exposure in a marine snail: A role
for p38 MAP kinase and downstream signaling cascades
Kevin Larade and Kenneth
B. Storey
Abstract
The
responses of members of the three main MAPK families (ERK, JNK/SAPK, p38 MAPK),
as well as selected peripheral pathways, were examined
in hepatopancreas of the marine periwinkle, Littorina
littorea, to determine if anoxia exposure influenced the
total protein content or the phosphorylation
status of any key components. The content of active phospho-p38 MAPK was 2-fold
higher in hepatopancreas from anoxic snails relative
to controls. A 1.7-fold increase in the amount of phospho-Hsp27 and a 1.3-fold
increase in phospho-CREB correlated well with the changes
in p38 MAPK phosphorylation. Activation of these factors via p38 MAPK may be
vital to the reorganization of metabolic responses to anoxia
in hepatopancreas. No changes in components of the JNK/SAPK and ERK pathways
occurred and transcription factors involved in lipid metabolism
did not appear to be affected by anoxia. The present analysis of a variety of
signaling pathways has implicated the p38 MAPK as a key anoxia-responsive
signal transduction pathway in L.
littorea.