LIMK1 regulates centrosome integrity and mitotic spindle positioning

Abstract

Actin cytoskeleton dynamics and proteins associated with actin cytoskeleton have been reported to play a role in regulating the cell cycle. LIM motif containing protein kinase 1 (LIMK1), a kinase involved in regulating actin cytoskeleton, has been reported to regulate cell cycle progression and associate with the centrosome during M-phase. However, the role of LIMK1 at the centrosome is not fully understood. Here, we reported that LIMK1 is involved in regulating centrosome integrity during M-phase. Cytoplasmic dynein light intermediate chain 1 and 2 (DYNC1LI1 and DYNC1LI2) are potential substrates functioning downstream of LIMK1 in centrosome integrity maintenance. LIMK1 mediated phosphorylation of DYNC1LIs could potentially regulate the transportation of centrosomal proteins to the spindle poles. Besides regulating centrosome integrity, LIMK1-Cofilin could potentially regulate the cortical actin network for proper spindle orientation and positioning.