THESIS DEFENSE — PUBLIC SEMINAR: ROLE OF MITOTIC KINESIN MKLP2 IN CYTOKINETIC ABSCISSION

Start Date & Time: 
Wednesday, 30 January, 2019 - 09:30
End Date & Time: 
Wednesday, 30 January, 2019 - 10:30
Venue: 

Amphitheatre, Level 2, Duke-NUS

Speaker: 
Speaker Details: 

FUNG SUET YIN SARAH
IBM PhD PROGRAM (INTAKE 2014)

Synopsis: 

At the onset of cytokinesis, nascent daughter cells do not simply divide. There are mechanisms in place to ensure equal and proper inheritance of genetic material into each daughter cell. Aurora B-mediated abscission checkpoint is a well-established mechanism that acts on the  ESCRT machinery to ensure  successful cytokinesis. However, the underlying mechanisms that control this checkpoint remain to be examined.

Firstly,  I will show that  the interplay of Aurora B kinase and B56-bound PP2A phosphatase activity on the kinesin motor protein MKlp2 controls abscission timing. Specifically, MKlp2 acts as a scaffolding protein that stabilizes microtubule cytoskeleton to the plasma membrane of dividing cells.

Secondly, I will demonstrate that MKlp2, through a previously uncharacterized domain known as the L6 Loop, controls remodeling of ESCRT-III complexes. Supporting this, deletion of the L6 loop leads to aberrant blebs surrounding the midbody and deformed ESCRT-III complexes.

Together, I propose that MKlp2 is a key mediator of cytokinesis and plays multiple roles during cytokinesis, acting both as a substrate of Aurora B kinase and as a regulator of ESCRT-III formation.

Thesis Advisor: Asst. Prof. Lee Sang Hyun and Prof. David Virshup