Abstract

Microtubules are involved in fundamental cellular processes, such as mitosis/meiosis, cell motility, intracellular transport and morphogenesis. Any perturbation in their functions causes a number of serious human diseases including birth defects and cancers. The key structure to the mechanism of the microtubule function is the MTOC (microtubule-organizing center), or centrosome which is composed of a pair of centrioles and the surrounding amorphous pericentriolar material. The centrosome controls the temporal and spatial distribution of microtubules, and recent evidence has indicated that cancer cells include centrosomes abnormal in structure and function. The purpose of our research is to understand how the centrosome regulates microtubule nucleation, orientation and anchorage at the molecular level. We have recently identified a novel centrosomal component (Cep135) present in a wide range of organisms. It is a structural protein involved in microtubule organization and spindle assembly during mitosis. Experiments are proposed to extend our studies on Cep135 in order to evaluate the working hypothesis that Cep135 is a matrix component of the centrosome important for maintenance of overall integrity of the pericentriolar material. Functional analysis will be done using both stable CHO cell lines expressing different forms of Cep135 and the Xenopus cell free extracts. The role of Cep135 in the process of bipolar spindle formation will be assessed in p53-deficient cells which contain multiple copies of centrosomes. Overexpression of Cep135 results in the formation of extraordinary filamentous structures in the centrosome; the nature of morphological defects caused by the change in the level of Cep135 will be determined using high resolution immunofluorescence microscopy and electron tomography. Finally, we will investigate the pattern of Cep135 interaction with other molecules in the centrosome, and a large Cep135-containing fraction identified in frog extracts will be further characterized.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM055735-02
Application #
6019276
Study Section
Cellular Biology and Physiology Subcommittee 1 (CBY)
Project Start
1998-07-01
Project End
2002-06-30
Budget Start
1999-07-01
Budget End
2000-06-30
Support Year
2
Fiscal Year
1999
Total Cost
Indirect Cost

  Institution

Name
University of Minnesota Twin Cities
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
168559177
City
Minneapolis
State
MN
Country
United States
Zip Code
55455

  Publications

Steere, Nathan; Chae, Vanessa; Burke, Michael et al. (2012) A Wnt/beta-catenin pathway antagonist Chibby binds Cenexin at the distal end of mother centrioles and functions in primary cilia formation. PLoS One 7:e41077
Steere, Nathan; Wagner, Michael; Beishir, Stephen et al. (2011) Centrosome amplification in CHO and DT40 cells by inactivation of cyclin-dependent kinases. Cytoskeleton (Hoboken) 68:446-58
Smith, Ewan; Hégarat, Nadia; Vesely, Clare et al. (2011) Differential control of Eg5-dependent centrosome separation by Plk1 and Cdk1. EMBO J 30:2233-45
Kuriyama, Ryoko (2009) Centriole assembly in CHO cells expressing Plk4/SAS6/SAS4 is similar to centriogenesis in ciliated epithelial cells. Cell Motil Cytoskeleton 66:588-96
Kuriyama, Ryoko; Bettencourt-Dias, Monica; Hoffmann, Ingrid et al. (2009) Gamma-tubulin-containing abnormal centrioles are induced by insufficient Plk4 in human HCT116 colorectal cancer cells. J Cell Sci 122:2014-23
Kuriyama, Ryoko; Terada, Yasuhiko; Lee, Kyung S et al. (2007) Centrosome replication in hydroxyurea-arrested CHO cells expressing GFP-tagged centrin2. J Cell Sci 120:2444-53
Soung, Nak-Kyun; Kang, Young Hwi; Kim, Keetae et al. (2006) Requirement of hCenexin for proper mitotic functions of polo-like kinase 1 at the centrosomes. Mol Cell Biol 26:8316-35
Blumer, Joe B; Kuriyama, Ryoko; Gettys, Thomas W et al. (2006) The G-protein regulatory (GPR) motif-containing Leu-Gly-Asn-enriched protein (LGN) and Gialpha3 influence cortical positioning of the mitotic spindle poles at metaphase in symmetrically dividing mammalian cells. Eur J Cell Biol 85:1233-40
Kuriyama, Ryoko; Besse, Colette; Geze, Marc et al. (2005) Dynamic organization of microtubules and microtubule-organizing centers during the sexual phase of a parasitic protozoan, Lecudina tuzetae (Gregarine, Apicomplexa). Cell Motil Cytoskeleton 62:195-209
Liu, Xiaoqi; Zhou, Tianhua; Kuriyama, Ryoko et al. (2004) Molecular interactions of Polo-like-kinase 1 with the mitotic kinesin-like protein CHO1/MKLP-1. J Cell Sci 117:3233-46

Showing the most recent 10 out of 16 publications