transposons induction triggers premature aging of oocytes.
Lin He, Professor
Molecular and Cell Biology
Closed. This professor is continuing with Spring 2024 apprentices on this project; no new apprentices needed for Fall 2024.
In mammals, female fertility is determined by the ovarian reserve of primordial follicles and the quality of mature MII oocytes. In humans, female fertility declines significantly after 35, with a rapid reduction in ovarian reserve and a severe deterioration in oocyte competence. On one hand, the pool of primordial follicles is established during the perinatal developmental stage and is rapidly depleted during reproductive aging. On the other hand, aging leads to a decline in oocyte quality, characterized by increased aneuploidy, mitochondrial defects, and elevated innate immune response. Despite the importance of oocyte aging, the underlying molecular mechanisms remain largely unclear.
Approximately 40% of the mouse genome originates from retrotransposons, which were historically viewed as parasitic invaders that are inactivated via degenerative mutations, as well as through transcriptional and post-transcriptional silencing. While retrotransposons are silenced in most somatic tissues, mature oocytes exhibit strong retrotransposon expression, accounting for 6-15% of the total transcriptome in mouse oocytes.
Previous studies from our lab have compared published RNA-seq data from young versus old mature oocytes in mice and have discovered a significantly altered retrotransposon expression profile during aging. In mice, an aberrant induction of specific retrotransposon families has been observed in aged, mature oocytes. The dynamic retrotransposon expression during oocyte aging, combined with the high level of retrotransposon expression in oocytes, suggests a functional role of retrotransposons in female reproductive aging.
Taken together, our lab is attempting to explain the cellular and molecular changes that occur during ovarian aging by collecting oocytes and ovaries at different stages and employing various omics methods.
Therefore, we are recruiting motivated undergraduates to test the ovary's phenotypes in genetic mouse models using histology techniques. Additionally, undergraduates who join this project will gain experience in mouse genetics, oocyte collection, immunohistochemistry, and immunofluorescence. Ideally, the student would commit to 15 hours per week.
Day-to-day supervisor for this project: Haiyuan Mu, Post-Doc
Hours: 12 or more hours
Related website: https://www.helabucb.org/
Biological & Health Sciences