P450 aromatase expression in germ cells and sperm of the adult mouse and rat testis and epididymis

Estrogen production within the testis has been a subject of substantial interest for years. Testicular germ cells and epididymal sperm have been hypothesized to be capable of synthesizing active P450 aromatase (P450arom), the estrogen synthesizing enzyme. This investigation was undertaken to establish that testicular germ cells and epididymal sperm contain active P450arom, to determine if P450arom mRNA is synthesized in germ cells, and to examine if there is a difference in the transcription of the P450arom gene between male germ cells and somatic cells. Specifically, the objectives of this research were: (1) to determine if adult mouse epididymal sperm contain active P450arom; (2) to determine if adult rat testicular germ cells and epididymal sperm contain active P450arom; (3) to determine if P450arom mRNA is expressed in adult rat germ cells; and (4) to determine if differences exist between germ cell and somatic cell P450arom transcripts. The major findings were: (1) adult mouse epididymal sperm contain active P450arom, and there is a decrease in the immunocytochemical expression and activity of P450arom in sperm as they traverse the epididymis; (2) adult rat testicular germ cells and epididymal sperm contain active P450arom, and there is a decrease in the immunocytochemical expression and activity of P450arom in sperm as they traverse the epididymis; and (3) P450arom mRNA is expressed in adult rat germ cells as early as the pachytene spermatocyte stage of development. These data clearly demonstrate that testicular germ cells of the adult mouse and rat are able to synthesize active P450arom, and that there is a decrease in P450arom expression in sperm as they undergo maturation in the epididymis. However, it has yet to be determined if the P450arom mRNA synthesized in germ cells is expressed differently than that in somatic cells. Differences between germ cell and somatic cell P450arom transcripts would suggest that germ cell P450arom mRNA is regulated differently and/or the resulting P450arom protein is unique. The research presented in this thesis establishes that testicular germ cells and epididymal sperm are capable of estrogen synthesis.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Biology, Molecular

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Janulis, Lynn Leslie

Contributors dc:contributor

• Bahr, Janice M.

• Biology, Molecular
• Biology, Animal Physiology

Statement dc:rights

• Copyright 1995 Janulis, Lynn Leslie

Language dc:language

eng

Identifier

AAI9624373
(UMI)AAI9624373

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/23845