Regulation of actomyosin contractility in the C. elegans zygote
Cortical contractility, driven by an actomyosin network underlying the plasma membrane, is responsible for the control of cell shape and the generation of contractile forces that drive polarization and cell division. Contractility depends on myosin activity as well as the organization of filamentous actin, which is determined by the concerted action of a multitude of actin binding proteins. Plastin/fimbrin is an evolutionary-conserved actin-bundling protein with two tandem repeats of calponin homology (CH) domains. To examine the role of C. elegans plastin, PLST-1, in early embryogenesis, we are characterizing the plst-1(tm4255) allele, a deletion that abrogates the third and fourth CH domains.