NTU Undergraduates' research April 2014 - Biosciences | Seite 51

Exaptation’s of MIR’s in Presenilin 2 Gene
Jade Leya Erwin
School of Science and Technology, Nottingham Trent University, Nottingham

ABSTRACT
Presenilin 2 (PSEN2) gene (Alzheimer’s Disease) in relation to locating the Transposable Element
(TE), the Mammalian Widespread Interspersed Repeat (MIR) within a range of species to see the
level of conservation. PSEN2 gene has an MIR3 subgroup within the Untranslated Region (UTR)
overlapping into the intronic space. Inverse orientation of this class of SINE (Short Interspersed
Repeat Element) shows to produce a splice site within the human gene and thus testing this against
other homologous species to see the level of conservation. Looking at the acceptor region of the MIR
as a way of investigating whether the PSEN2 was predestined to contain the MIR. Previous studies
showing the MIR to be contained within dendritic rich areas of neurons in comparison to the cell body
has been evidence towards the MIR being found within these genes located in the UTR (5’ and 3’)
and thus showing that the MIR may be offering some role within these particular genes. With this in
mind, will the MIR also present some functional exaptation of the PSEN2 gene with offering a splice
site and multiple mRNA variants in a range of species with a location within the 5’ UTR? This will be
investigated in the presence of the variants in a range of human and mouse tissues to get an idea of the
significance the MIR is bringing to the PSEN2 gene and possible exaptation into the protein. Mouse
with considerable interest due to the analysis and sequencing of the mouse genome being recently
accomplished, the similarities and difference may be key in understanding this disease linked gene
and have significance due to the use of mice as models in the study of Alzheimer’s.
Summary: PSEN2 containing MIRs (SINE element) will be identified and mammalian orthologes
will be extracted from sequence databases for multiple sequence alignment. Expression of PSEN2
variants will be investigated in a range of tissues for both mouse and human to research into the
exaptation of the protein with the presence of the MIR creating the alternative splice variants.
Keywords;
MIR, EST, PSEN2, alternative splicing, cDNA, SINE, Exaptation’s, mRNA