The role of integrins in hair cell precursor differentiation.
Doctoral thesis, UCL (University College London).
The inner ear sensory epithelium of the organ of Corti is a multicellular structure which detects sound. The inner ear develops from the otic vesicle which contains all the information required for the cells to differentiate and generate all the cell subtypes found in the mature organ of Corti. Organogenesis of the inner ear is a complex process involving different cell functions including cell proliferation and differentiation, all of which are regulated by a network of different factors. Cell adhesion is one of the crucial biological events required by the cells for differentiation. Integrins are the main receptors for adhesion to the extracellular matrix (ECM). The aim of this work was to elucidate the roles of integrins in the differentiation process that occurs in both the organ of Corti and in OC-2 cells; cells that are derived from an immature murine organ of Corti. Immunohistochemistry in mature organ of Corti showed that r31-integrin was expressed in both supporting and hair cells, meanwhile av-integrin was localised mainly in the region of the hair cells. In vitro, αv-, β3-and β1-integrins and the hair cell markers myosin VI and VIIa were expressed at significantly higher levels in differentiated OC-2 cells when compared with undifferentiated OC-2 cells. Furthermore, myosin VI and VIIa were used to monitor the differentiation process occurring in OC-2 cells. siRNA, used to inhibit expression of integrin subunits in differentiated OC-2 cells, was able to decrease the level of expression of myosin VI and VIIa to values comparable with undifferentiated OC-2 cells. Furthermore, the induction of β3-integrin subunit in undifferentiated OC-2 cells was able to increase the expression of myosin VIIa to values comparable with differentiated OC-2 cells, suggesting that this specific integrin subunit possibly is involved directly in the differentiation process in OC-2 cells.
|Title:||The role of integrins in hair cell precursor differentiation|
|Additional information:||Authorisation for digitisation not received|
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