Physical and Chemical Basis of Cytoplasmic Streaming

INTRODUCTION ........................................................................................................ 206 SHUTI’LE STREAMING IN THE MYXOMYCETE PLASMODIUM ................ 207 General ...................................................................................................................... 207 Contractile Properties of the Plasmodial Strand ...................................................... 208 Activation caused by stretching .................................................................................. 208 Activation caused by loading .................................................................................... 209 Synchronization of local ,hythms .............................................................................. 209 Contractile Proteins .................................................................................................. 210 Plasmodium actomyosin .......................................................................................... 210 Plusmodium myosin ................................................................................................ 210 Plusmodium actin .................................................................................................... 211 Tension Production of Reconstituted Actomyosin Threads from Physarum ............ 212 Regulation f Movement .......................................................................................... 213 The role of Ca ~ ...................................................................................................... 213 The role of ATP ...................................................................................................... 214 Structural Basis of MotiliO~ ...................................................................................... 216 Contraction-relaxation cycleand actln transformations ................................................ 216 FibrillogenesiS ........................................................................................................ 217 Birefringence .......................................................................................................... 217 Summary .................................................................................................................. 218 ROTATIONAL STREAMING IN CHARACEAN CELLS .................................... 219 General ...................................................................................................................... 219 The Site of Motive Force Generation ........................................................................ 219 Subcortical Filaments, Their Identification as Actin, and Their Indispensability for Streaming .......................................................................................... 220 Nitella Myosin and its Localization i the Cell ...................................................... 221 Motility of Fibrils and Organelles in Isolated Cytoplasmic Droplets ...................... 222 Rotation f chloroplasts ............................................................................................ 222 Motile fibrils .......................................................................................................... 223