Salinity is one of the major environmental factors limiting
growth and productivity of rice plants. In this study, the
effect of salt stress on phospholipid signaling responses in
rice leaves was investigated. Leaf cuts were radiolabeled
with 32 P-orthophosphate and the lipids extracted and
analyzed by thin-layer chromatography, autoradiography
and phosphoimaging. Phospholipids were identifi ed by
co-migration of known standards. Results showed that
32 P i was rapidly incorporated into the minor lipids, phosphatidylinositol
bisphosphate (PIP 2 ) and phosphatidic
acid (PA) and, interestingly, also into the structural lipids
phosphatidylethanolamine (PE) and phosphatidylglycerol
(PG), which normally label relatively slowly, like
phosphatidylcholine (PC) and phosphatidylinositol (PI).
Only very small amounts of PIP 2 were found. However, in
response to salt stress (NaCl), PIP 2 levels rapidly (