A new role for the tumour suppressor LIN-35 during meiotic recombination in Caenorhabditis elegans

• Main Author: Lohn, Zoe Roy
• Language: English
• Published: University of British Columbia 2010
• Online Access: http://hdl.handle.net/2429/27276

Meiosis is a fundamental biological process used by sexually reproducing species to ensure the faithful transmission of genetic material and to generate genetic diversity. In humans, failure to recombine properly during meiosis causes genetic conditions in the human conceptus such as aneuploidy and spontaneous abortion. An excellent model organism for the investigation of meiotic recombination is the nematode, Caenorhabditis elegans, which has many conserved meiotic processes. In this thesis, I have investigated the role of lin-35 in meiotic crossing over. LIN-35 is the C. elegans ortholog of the retinoblastoma (Rb) protein, well characterized with respect to its role in gene transcription and cell proliferation. My results show that mutation in the lin-35 gene alters recombination frequency differentially for several regions of the chromosome, causing increases in recombinationally suppressed regions and decreases in highly recombinogenic regions. In combination with Rec-1, a mutant known to alter crossover distribution, crossovers across the length of the entire chromosome, were decreased. In addition, other severely detrimental phenotypes were observed. For example, gametic viability was reduced dramatically in the double mutant, compared to either mutant alone. Thus, the Lin-35 and Rec-1 phenotypes were synergistic, indicating non-redundancy. In summary, lin-35 function plays a role in achieving normal levels of meiotic recombination, a role that may be related to its function in chromatin modification and gene transcription.