Use this URL to cite or link to this record in EThOS:
Title: Establishing polarity : staufen protein and interacting factors
Author: Adams, J. H. J.
Awarding Body: University of Cambridge
Current Institution: University of Cambridge
Date of Award: 2000
Availability of Full Text:
Full text unavailable from EThOS.
Please contact the current institution’s library for further details.
The work presented here describes the identification of interacting factors with STAUFEN protein, necessary for the transport, anchoring or translation of the above transcripts. Analysis of staufen alleles, deletion constructs and sequence comparison of homologues revealed two functional areas within the protein that are likely to mediate protein-protein interaction: dsRBD2 and dsRBD5. Domain5 although conserved, does not bind to dsRNA. However it is necessary to anchor askar and bicoid mRNA at their target regions within the Drosophila egg, and to localise prospero mRNA during neurogenesis. A yeast interaction-screen to search for binding partners of STAUFEN protein identified three proteins that interact with dsRBD5: MIRANDA, STAUFEN and WELFEN. I show that STAUFEN and MIRANDA interact as part of a conserved gene cassette, used in oogenesis and neurogenesis in Drosophila, to localise transcripts encoding for homeobox transcription factors - bicoid mRNA to the anterior of the oocyte/egg and prospero mRNA to the basal side of neuroblasts. Temporal misexpression of a MIRANDA-GFP fusion protein during oogenesis leads to localisation of askar mRNA to the anterior pole of the oocyte, demonstrating its ability to anchor a STAUFEN/mRNA complex at the anterior of the oocyte. STAUFEN protein also interacts with itself through dsRBD5. An isolated dsRBD5 can dimerise in yeast, and in vitro. In a yeast based mutagenesis assay I identified several residues in dsRBD5 that are necessary for dimerisation, or the interaction with WELFEN, a novel 413 amino acids protein. A possible role for dimerisation, or binding WELFEN, might be translational control or anchoring of either askar or bicoid mRNA within the oocyte.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available