Evidence for accumulation of a 55 kDa stress-related protein in rice and several other plant genera

Abstract

Rice cells synthesize a 87 kDa protein (SAP 87) which cross-reacts with anti Neurospora crassa HSP 80 antibodies. Apart from SAP 87, we show that a polypeptide of 55 kDa of rice cross-reacts with these antibodies. This 55 kDa polypeptide is accumulated in response to high and low temperatures, salinity and desiccation stress conditions in shoots of rice seedlings. Apart from rice, Triticum aestivum, Sorghum bicolor, Pisum sativum, Zea mays and Brassica juncea seedlings also showed accumulation of the 55 kDa polypeptide in response to high temperature stress on Western blots. Importantly, anti human HSP 56 antibodies showed cross-reaction with a major high temperature induced 55 kDa protein of rice that matched in position to the 55 kDa protein which cross-reacted with anti N. crassa HSP 80 antibodies.