Sangam: A Confluence of Knowledge Streams

The function and regulation of myosin-interacting guanine nucleotide exchange factor (MYOGEF) and centrosome/spindle pole associated protein (CSPP) during mitotic progression and cytokinesis

Show simple item record

dc.creator Asiedu, Michael Kwabena
dc.date 2007-11-27T16:50:57Z
dc.date 2007-11-27T16:50:57Z
dc.date 2007-11-27T16:50:57Z
dc.date 2007
dc.date December
dc.date.accessioned 2023-04-10T10:09:40Z
dc.date.available 2023-04-10T10:09:40Z
dc.identifier http://hdl.handle.net/2097/436
dc.identifier.uri http://localhost:8080/xmlui/handle/CUHPOERS/285467
dc.description Doctor of Philosophy
dc.description Biochemistry Interdepartmental Program
dc.description Qize Wei
dc.description This dissertation describes the role of myosin-interacting guanine nucleotide exchange factor (MyoGEF) and centrosome/spindle pole associated protein (CSPP) in mitotic progression and cytokinesis. We have identified three mouse isoforms of CSPP, all of which interact and colocalize with MyoGEF to the central spindle in anaphase cells. The N-terminus of MyoGEF interacts with myosin whereas the C terminus interacts with the N-terminus of CSPP, forming a complex. The N-terminus of CSPP appears to be important for both localization and interaction with MyoGEF. CSPP plays a role in mitotic progression since its depletion by RNAi resulted in metaphase arrest. MyoGEF is required for completion of cytokinesis. Both MyoGEF and CSPP are phosphorylated by mitotic kinases including Plk1 and Aurora. Importantly, MyoGEF is phosphorylated at Thr-574 in mitosis by Polo-like kinase 1, and this phosphorylation is required for activation of RhoA. Thr-543 of MyoGEF is required for Plk1 binding in mitosis and phosphorylation of MyoGEF by Cdk1/cyclinB, possibly at Thr-543 may generate a Plk1 docking site, i.e., Cdk1 can phosphorylate MyoGEF at Thr-543, thereby allowing Plk1 to bind and phosphorylate MyoGEF at Thr-574. Finally, MyoGEF and CSPP are also phosphorylated by Aurora-B kinase in vitro. Taken together, we propose that Aurora-B may phosphorylate and recruit MyoGEF and CSPP to the central spindle, where phosphorylation of MyoGEF at Thr-543 promotes Polo kinase binding and additional phosphorylation of MyoGEF, leading to the activation of RhoA at the cleavage furrow.
dc.format video/mpeg
dc.format video/mpeg
dc.format video/mpeg
dc.format video/mpeg
dc.format video/mpeg
dc.format application/pdf
dc.language en_US
dc.publisher Kansas State University
dc.subject Guanine nucleotide exchange factor
dc.subject MyoGEF
dc.subject Centrosome proteins
dc.subject Cytokinesis
dc.subject Mitotic kinases
dc.subject Mitotic progression
dc.subject Biology, Cell (0379)
dc.subject Chemistry, Biochemistry (0487)
dc.title The function and regulation of myosin-interacting guanine nucleotide exchange factor (MYOGEF) and centrosome/spindle pole associated protein (CSPP) during mitotic progression and cytokinesis
dc.type Dissertation


Files in this item

Files Size Format View
MichaelAsiedu2007.pdf 1.925Mb application/pdf View/Open
MOVIE S1.mpg 1.372Mb video/mpeg View/Open
MOVIE S2.mpg 6.571Mb video/mpeg View/Open
MOVIE S3.mpg 1.392Mb video/mpeg View/Open
MOVIE S4.mpg 375.5Kb video/mpeg View/Open
MOVIE S5.mpg 1.764Mb video/mpeg View/Open

This item appears in the following Collection(s)

Show simple item record

Search DSpace


Advanced Search

Browse