| Dissertation |
Thesis (Ph.D.) --NUI, 2009 at Department of Anatomy, UCC. |
| Summary |
The differentiation of neuroepithelial progenitor cells into the neurons and glial cells of the CNS is a complex process. The molecular mechanisms which influence the fate of the cells of the CNS have been studied for a long time and new factors, such as the recently identified microRNAs (miRNAs), are continuing to add to the intricacy of CNS development. MiRNAs were first discovered in C. elegans in 1993 and since then hundreds of evolutionarily conserved miRNAs have been identified. MiRNAs are small non-coding RNAs, 19-24bp in length, and they have been implicated in many biological processes. MicroRNAs are not only expressed in a tissue specific manner but are also restricted to individual cell types within specific tissues and they are thought to act as post-transcriptional modulators of gene expression. Many mRNA targets of miRNAs have been identified using bioinformatical approaches, however, few have been proven experimentally. In this project our first study looked at the expression of three CNS specific miRNAs in the developing spinal cord, mir23a, which is astrocyte specific, mir124a and mir128a, which are both neuron specific. Subsequent experiments went on to examine the transcription factor Sox9 as a potential target of mir124a. Sox9 is a member of the Sox family of transcription factors and has been connected with numerous developmental processes. It is strongly expressed in neural stem cells and then in glial cells of the CNS and has been implicated as a component of the mechanism that causes the switch from neurogenesis to gliogenesis. Mir124a on the other hand is expressed in neurons of the CNS, and is one of the most well known and studied miRNAs. It was our hypothesis that a potential mechanism for neurogenesis in the developing spinal cord is the suppression of Sox9 by mir124a. |
| Subject |
RNA.
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| Collection |
Theses Ph.D.
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Theses Anatomy Department
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| Description |
168 p. : ill. ; 30 cm. |
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