The small GTPase Rheb is required for spermatogenesis but not oogenesis

M. D. Baker, M. Ezzati, G. M. Aloisio, E. D. Tarnawa, I. Cuevas, Y. Nakada, D. H. Castrillon

Research output: Contribution to journalArticle

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Abstract

The process of germ cell development is under the tight control of various signaling pathways, among which the PI3K-Akt-mTOR pathway is of critical importance. Previous studies have demonstrated sex-specific roles for several components of this pathway. In the current study, we aimed to evaluate the role of Rheb, a member of the small GTPase superfamily and a critical component for mTORC1 activation, in male and female gametogenesis. The function of Rheb in development and the nervous system has been extensively studied, but little is known about its role in the germ line.We have exploited genetic approaches in the mouse to study the role of Rheb in the germ line and have identified an essential role in spermatogenesis. Conditional knockout (cKO) of Rheb in the male germ line resulted in severe oligoasthenoteratozoospermia and male sterility. More detailed phenotypic analyses uncovered an age-dependent meiotic progression defect combined with subsequent abnormalities in spermiogenesis as evidenced by abnormal sperm morphology. In the female, however, germ-cell specific inactivation of Rheb was not associated with any discernible abnormality; these cKO mice were fertile with morphologically unremarkable ovaries, normal primordial follicle formation, and subsequent follicle maturation. The absence of an abnormal ovarian phenotype is striking given previous studies demonstrating a critical role for the mTORC1 pathway in the maintenance of primordial follicle pool. In conclusion, our findings demonstrate an essential role of Rheb in diverse aspects of spermatogenesis but suggest the existence of functionally redundant factors that can compensate for Rheb deficiency within oocytes.

Original languageEnglish (US)
Pages (from-to)615-625
Number of pages11
JournalReproduction
Volume147
Issue number5
DOIs
StatePublished - 2014

Fingerprint

Oogenesis
Monomeric GTP-Binding Proteins
Spermatogenesis
Germ Cells
Gametogenesis
Oligospermia
Critical Pathways
Male Infertility
Phosphatidylinositol 3-Kinases
Knockout Mice
Nervous System
Oocytes
Spermatozoa
Ovary
Maintenance
Phenotype

ASJC Scopus subject areas

  • Obstetrics and Gynecology
  • Reproductive Medicine
  • Embryology
  • Endocrinology
  • Cell Biology
  • Medicine(all)

Cite this

Baker, M. D., Ezzati, M., Aloisio, G. M., Tarnawa, E. D., Cuevas, I., Nakada, Y., & Castrillon, D. H. (2014). The small GTPase Rheb is required for spermatogenesis but not oogenesis. Reproduction, 147(5), 615-625. https://doi.org/10.1530/REP-13-0304

The small GTPase Rheb is required for spermatogenesis but not oogenesis. / Baker, M. D.; Ezzati, M.; Aloisio, G. M.; Tarnawa, E. D.; Cuevas, I.; Nakada, Y.; Castrillon, D. H.

In: Reproduction, Vol. 147, No. 5, 2014, p. 615-625.

Research output: Contribution to journalArticle

Baker, MD, Ezzati, M, Aloisio, GM, Tarnawa, ED, Cuevas, I, Nakada, Y & Castrillon, DH 2014, 'The small GTPase Rheb is required for spermatogenesis but not oogenesis', Reproduction, vol. 147, no. 5, pp. 615-625. https://doi.org/10.1530/REP-13-0304
Baker MD, Ezzati M, Aloisio GM, Tarnawa ED, Cuevas I, Nakada Y et al. The small GTPase Rheb is required for spermatogenesis but not oogenesis. Reproduction. 2014;147(5):615-625. https://doi.org/10.1530/REP-13-0304
Baker, M. D. ; Ezzati, M. ; Aloisio, G. M. ; Tarnawa, E. D. ; Cuevas, I. ; Nakada, Y. ; Castrillon, D. H. / The small GTPase Rheb is required for spermatogenesis but not oogenesis. In: Reproduction. 2014 ; Vol. 147, No. 5. pp. 615-625.
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