A sorghum 85 kDa heat stress-modulated protein shows calmodulin-binding properties and cross-reactivity to anti-Neurospora crassa Hsp 80 antibodies

The present study, carried out to identify stress-modulated calmodulin (CaM)-binding proteins in sorghum, resulted in the isolation of several proteins, which showed binding to CaM-Sepharose matrix. Calmodulin gel overlay assay and MALDI-ToF MS analysis revealed that an 85 kDa protein (Hsp85), which interacted with calmodulin, cross-reacted with anti-N. crassa Hsp80 antibodies. Since these antibodies bind to plant Hsp90, sorghum Hsp85 is likely to be a member of the Hsp90 family. This study provides the first evidence that a member of Hsp90 (Hsp85) in plants exhibits CaM-binding properties.