Expression and subcellular localization of a membrane protein related to Hsp30p in Saccharomyces cerevisiae.

The Saccharomyces cerevisiae YDR033w gene product is homologous to Hsp30p and Yro2p, both of which are induced during heat shock. To investigate the subcellular localization of the YDR033w gene product, hemagglutinin (HA) epitope-tagged protein was expressed, detected on immunoblots, and localized by immunofluorescence to cell membranes, primarily the plasma membrane. A punctuate immunofluorescence pattern was observed within cell buds. The nuclear envelope, but not the vacuole or mitochondrial membranes, were also immunostained. We refer to YDR033w as MRH1 to denote that it encodes a membrane protein related to Hsp30p.