Use this URL to cite or link to this record in EThOS:
Title: An investigation of the mechanism of histone mRNA 3' end formation in the nematode Caenorhabditis elegans
Author: Whitelaw, Sandra
ISNI:       0000 0001 3567 3078
Awarding Body: University of Aberdeen
Current Institution: University of Aberdeen
Date of Award: 2006
Availability of Full Text:
Access from EThOS:
In animals, the majority of replication-dependent histone mRNAs end in a highly conserved hairpin structure having undergone histone specific cleavage instead of polyadenylation.  The cleavage occurs between the hairpin and the histone downstream element (HDE) present in the 3’ untranslated region (3’ UTR).  This process involves factors including the hairpin-binding protein that binds to the hairpin, and the U7 snRNA that is complementary to and binds to the HDE. The terminal exon of Caenorhabditis elegans histone genes contains three highly conserved sequence elements: the hairpin, an AATCC element and a typical polyadenylation signal.  It was determined that both the histone-specific elements and the polyadenylation signal are present in histone mRNA suggesting that histone mRNA can undergo both histone-specific cleavage and to a less extent polyadenylation. Knocking down the expression of the hairpin-binding protein CDL-1 within C. elegans by RNAi inhibits histone synthesis.  However cdl-1(RNAi) does not affect histone mRNA levels, or the structure of selected histone mRNA 3’ ends, indicating that the main role of CDL-1 may be in translational control. A C. elegans U7 snRNA candidate was identified and bioinformatic analysis identified a number of similarities between the candidate and other snRNAs.  However experimental analysis concluded that the candidate sequence was not expressed in C. elegans. A number of candidate U7 snRNA specific proteins were identified all of which contained similarity to the Sm motifs of other Sm/Lsm proteins.  RNAi analysis of the three candidates did not lead to a distinct phenotype.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available