MAIZE SEEDLINGS SHOW CELL-SPECIFIC RESPONSES TO HEAT-SHOCK AS REVEALED BY EXPRESSION OF RNA AND PROTEIN

The cellular localization of heat-shock proteins has been described in a number of experimental animal systems but is not well defined in pl ant systems. Sense and antisense RNA transcripts from the open reading frame (ORF) of 18-kDa maize heat-shock protein genes were employed in in situ hybridizations of inbred Oh43 radicles and plumules to reveal the locations of their mRNAs. Localization of the specific mRNAs to t he younger meristematic cells of the root-tips and shoot-tips and also to the densely cytoplasmic cells of the vasculature was observed rout inely. The ORF of one of our 18-kDa genes was cloned into an expressio n vector, and the 161-amino acid polypeptide was used to raise antibod ies. Using a Fast Red procedure, the cellular positions of the heat-sh ock protein-antibody conjugates were observed in sections similar to t hose employed in the antisense RNA in situ hybridizations. The localiz ation of the antibody appears to parallel closely the patterns of dist ribution of the mRNAs. (C) 1996 Wiley-Liss, Inc.