AGO Argonautes in spermatogenesis
| dc.contributor.author | Johnstone, Jessica P | |
| dc.date.accessioned | 2025-02-18T17:22:06Z | |
| dc.date.available | 2025-02-18T17:22:06Z | |
| dc.date.issued | 2023-05-25 | |
| dc.description | Honors Thesis Presented to the College of Agriculture and Life Sciences, Cornell University in Partial Fulfillment of the Requirements for the Biological Sciences Honors Program | |
| dc.description.abstract | Of the four different Argonaute proteins from the AGO family (AGO) present in mice, previous work from the Cohen Lab has identified that AGO3 and AGO4 are found in the nucleus of male germline cells during spermatogenesis and that knockout(KO) Ago4 male mice have a subfertility phenotype along with the upregulation of AGO3 protein localization. This upregulation suggests that AGO4 and AGO3 might have overlapping function(s) in the germline. The main goal of this study is to investigate the role of AGO proteins during spermatogenesis, specifically their function in prophase I of meiosis. Two mutant mouse lines were utilized: a triple knockout mouse line (Ago413 KO) and a single knockout mouse line, Ago3 KO. Prophase I spreads were performed on homozygous mutant Ago413 KO males, to investigate if meiotic sex chromosome inactivation (MSCI), a characteristic feature of meiotic prophase I, occurs properly since our previous studies indicated a requirement for AGO4 in these events. Spreads revealed the mislocalization of BRCA1, TOPBP1, and γH2AX, known sex-body markers, supporting a role for one or more of these AGOs in MSCI and meiotic prophase I. To narrow down a specific role for AGO3, I investigated the fertility of Ago3 KO males. Spermatozoa numbers and function were assessed with computer assisted sperm analysis (CASA). Surprisingly, homozygous mutant Ago3 KO mice had both normal sperm counts and testis weight when compared to wild-type (WT) mice. However, the Ago3 KO mice show abnormal testis architecture, supporting that there may be a role for AGO3 in spermatogenesis. | |
| dc.identifier.doi | https://doi.org/10.7298/tnf2-2c37 | |
| dc.identifier.uri | https://hdl.handle.net/1813/116709 | |
| dc.language.iso | en_US | |
| dc.subject | Spermatogenesis | |
| dc.subject | Argonautes | |
| dc.title | AGO Argonautes in spermatogenesis | |
| dc.type | dissertation or thesis | |
| schema.accessibilityFeature | alternativeText |
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