Stg1 is a novel SM22/transgelin-like actin-modulating protein in fission yeast

We identified a novel actin-modulating protein Stg1 in the fission yeast Schizosaccharomyces pombe. Stg1 is similar to mammalian SM22/transgelin, and biochemical experiments showed that Stg1 crosslinked F-actin. Microscopic observation suggested that Stg1 was a component of actin patch. Overexpression of Stg1 caused a defect in cytokinesis by suppressing the formation of a contractile ring and formation of abnormal aggregates of F-actin in the ends and mid-region of cells. Although distribution of the actin cytoskeleton was not affected by disrupting stg1+, genetic interaction suggested that Stg1 was likely involved in controlling the organization of the actin cytoskeleton in cell morphogenesis and cytokinesis in fission yeast.