Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.641653
Title: The I factor 5'UTR : physical properties and possible role in epigenetic control
Author: Bisoni, Laura
Awarding Body: University of Edinburgh
Current Institution: University of Edinburgh
Date of Award: 1999
Availability of Full Text:
Access through EThOS:
Full text unavailable from EThOS. Please try the link below.
Access through Institution:
Abstract:
The I factor is a Long Interspersed Nuclear Element of Drosophila melanogaster. Transposition of the I factor occurs via an RNA intermediate and is restricted to the germline of hybrid females that have received one half of their chromosome complement from a parent devoid of active I factors. If the I factor devoid chromosomes are of maternal origin, I factor transposition is associated with lethality of the F2 embryos and high frequency of lethal mutations in the F3 generation. In contrast to its restricted pattern of transposition, I factor expression is detectable in somatic issues of all flies that carry active I factors. Accumulation of I factor copies over the generations is associated with cessation of transposition and a decrease in expression in the female germline. As previously shown, the I factor 5' Untranslated Transcribed Region (UTR) can impose on a reporter gene a pattern of expression similar to that observed for complete I factors, i.e. high levels of expression in the germline of permissive females and lower yet significant levels in other tissues and in males. Furthermore, the I factor 5'UTR is sensitive to the presence of complete I factors and multiple copies of this sequence significantly reduce of the F2 lethality associated with I factor transposition. This work investigates the role of the 5' UTR in determining parental effects and in mediating processes of Polycomb-dependent I factor silencing. In addition, the possibility that the high Adenine-Thymine content of the 5'UTR might impose on this sequence an unusual conformation that could be responsible for some of the biological properties of the I factor is also investigated.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.641653  DOI: Not available
Share: