Amoeboid Motility without Actin: Insights into the Molecular Mechanism of Locomotion Using the Major Sperm Protein (MSP) of Nematodes

The amoeboid cell motility of the nematode sperm cytoskeleton was studied in terms of the 14-kD major sperm protein (MSP) rather than on actin. The locomotive system was believed to be produced by the vectorial assembly of MSP filaments and their bundled arrangement into macrofibers with the absence of motor proteins. An in vitro motility system was developed wherein MSP filament arrangement was able to move membrane vesicles. Locomotion required a soluble factor in addition to MSP, membrane vesicles and adenosine triphosphate.