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Roles of the Mother Centriole Appendage Protein Cenexin in Microtubule Organization during Cell Migration and Cell Division: A Dissertation
Faculty Advisor
Stephen Doxsey, PhDAcademic Program
Interdisciplinary Graduate ProgramUMass Chan Affiliations
Program in Molecular MedicineDocument Type
Doctoral DissertationPublication Date
2016-08-03Keywords
Dissertations, UMMSHeat-Shock Proteins
Cell Division
Cell Movement
Cell Polarity
Centrioles
Centrosome
Endosomes
Epithelial Cells
Microtubule-Organizing CenterMicrotubulesHeat-Shock ProteinsCell DivisionCell MovementCell PolarityCentriolesCentrosomeEndosomesEpithelial CellsMicrotubule-Organizing CenterMicrotubulesCenexinCell BiologyCellular and Molecular Physiology
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Show full item recordAbstract
Epithelial cells are necessary building blocks of the organs they line. Their apicalbasolateral polarity, characterized by an asymmetric distribution of cell components along their apical-basal axis, is a requirement for normal organ function. Although the centrosome, also known as the microtubule organizing center, is important in establishing cell polarity the mechanisms through which it achieves this remain unclear. It has been suggested that the centrosome influences cell polarity through microtubule cytoskeleton organization and endosome trafficking. In the first chapter of this thesis, I summarize the current understanding of the mechanisms regulating cell polarity and review evidence for the role of centrosomes in this process. In the second chapter, I examine the roles of the mother centriole appendages in cell polarity during cell migration and cell division. Interestingly, the subdistal appendages, but not the distal appendages, are essential in both processes, a role they achieve through organizing centrosomal microtubules. Depletion of subdistal appendages disrupts microtubule organization at the centrosome and hence, affects microtubule stability. These microtubule defects affect centrosome reorientation and spindle orientation during cell migration and division, respectively. In addition, depletion of subdistal appendages affects the localization and dynamics of apical polarity proteins in relation to microtubule stability and endosome recycling. Taken together, our results suggest the mother centriole subdistal appendages play an essential role in regulating cell polarity. A discussion of the significance of these results is included in chapter three.DOI
10.13028/M2QC73Permanent Link to this Item
http://hdl.handle.net/20.500.14038/32215Rights
Copyright is held by the author, with all rights reserved.Scopus Count
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