Actin cytoskeleton in cell polarity and asymmetric division during mouse oocyte maturation.

Mammalian oocyte maturation involves two successive rounds of extremely asymmetric cell divisions (known as polar body extrusion) to generate a functional haploid egg. Successful polar body extrusion relies on establishment of an asymmetric spindle position and cortical polarity. Decades of studies using mouse oocytes as a model have revealed critical roles for a dynamic actin cytoskeleton in this process. Here, we review the contribution of actin to the critical events during oocyte meiotic cell divisions with an emphasis on recent advances in understanding the underlying molecular and physical mechanisms.