LE3 .A278 2019

2019

Stewart, Don

Acadia University

Bachelor of Science

Honours

Biology

Biology

Doubly uniparental inheritance (DUI) is an unusual system of mitochondrial DNA (mtDNA) inheritance found only in some bivalves. Under DUI, two distinct gender-associated mtDNA lineages exist, one that is paternally transmitted through sperm (M-type) and one that is maternally transmitted through eggs (F-type). Role reversal events occur periodically in which an F type mt genome recombines with an M-type control region, which facilitates the recombinant genome entry into the paternal route of transmission. Because the male control region (CR) is always transferred during role reversal/recombination events it is thought to play an integral role in the transmission of mtDNA through male mussels. Additional DUI-positive species need to be studied to characterize molecular signals in the CR that play a role in maintaining DUI. The strategy for amplifying the male mitochondrial genome of Geukensia demissa, a mussel in the family Mytilidae, was to amplify and sequence part of the cytochrome oxidase subunit III (cox3) gene and use the resulting sequence for designing primers for use in Long-Range PCR to amplify the whole genome in large fragments. A partial coding sequence for male cox3 mtDNA was obtained and used to design primers that amplified a ~12 kb fragment of the male mitochondrial genome (~ three-quarters of the mt genome), by LR PCR. The remaining putative region of male mtDNA between cox3 and 16SrRNA was not successfully amplified. The ~12 kb fragment was sequenced by Pacific Biosciences RS II sequencing technology (Génome Québec, McGill). A putative partial male mt genome was assembled and edited from PacBio circular consensus reads using Geneious v.2019.1. The partial male G. demissa mitochondrial genome was annotated using MITOS and Geneious and compared to female G. demissa mtDNA obtained by a previous honours student. The complete male mtDNA sequence will be required for definitive identification of the control region and a comprehensive comparison with the female mt genome.

The author retains copyright in this thesis. Any substantial copying or any other actions that exceed fair dealing or other exceptions in the Copyright Act require the permission of the author.

https://scholar.acadiau.ca/islandora/object/theses:3272