Normal actin cytoskeleton organization in budding yeast requires the function of the Pan1p/ End3p complex. Mutations in PAN1 and END3 cause defects in the organization of actin cytoskeleton and endocytosis. By screening for mutations that can suppress the temperature sensitivity of a pan1 mutant (pan1-4), a novel serine/threonine kinase Prk1p is now identified as a new factor regulating the act...

A conditioning treatment of 30 min at 42 degrees C or 43 degrees C, followed by a 4-h recovery period at 37 degrees C, induces thermotolerance state in the cytoskeleton of Reuber H35 hepatoma cells and N2A neuroblastoma cells. Evidence for the involvement of heat shock proteins in the development of thermotolerance in the cytoskeleton has been obtained from the following observations: only thos...