Actin polymerization often occurs at the plasma membrane to drive the protrusion of lamellipodia and filopodia at the leading edge of migrating cells.
A role for actin polymerization in another cellular process that involves the reshaping of the plasma membrane, namely endocytosis, has recently been established.
Pathology of actin polymerization
Lowe syndrome (mutations in the OCRL1 gene, which encodes a phosphatidylinositol 4,5 bisphosphate 5-phosphatase) (12428211)
References
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