SF-assemblin, striated fibers, and segmented coiled coil proteins

The flagellar basal apparatus of many flagellate green algae contains nonco ntractile striated microtubule-associated fibers (SMAFs). The SMAFs consist of 2-nm protofilaments and are predominantly built from striated fiber (SF )-assemblin, an acidic 33-kDa protein. In this review we summarize the pres ent knowledge concerning the biochemical properties of SF-assemblin and the molecular architecture of the SMAFs, provide evidence for homologous prote ins and similar filament systems in other eukaryotes, and, finally, discuss possible biological functions of SF-assemblin. (C) 1998 Wiley-Liss, Inc.