The RHOX homeodomain proteins regulate the expression of insulin and other metabolic regulators in the testis.

Defects in cellular metabolism have been widely implicated in causing male infertility, but there has been little progress in understanding the underlying mechanism. Here we report that several key metabolism genes are regulated in the testis by Rhox5, the founding member of a large X-linked homeobox gene cluster. Among these Rhox5-regulated genes are insulin 2 (Ins2), resistin (Retn), and adiponectin (Adipoq), all of which encode secreted proteins that have profound and wide-ranging effects on cellular metabolism.

Follicle-stimulating hormone induces multiple signaling cascades: evidence that activation of Rous sarcoma oncogene, RAS, and the epidermal growth factor receptor are critical for granulosa cell differentiation.

FSH regulates ovarian granulosa cell differentiation not only by activating adenylyl cyclase and protein kinase A (PKA) but also by other complex mechanisms. Using primary rat granulosa cell cultures, we provide novel evidence that FSH rapidly activates two small GTP-binding proteins RAP1 and RAS. FSH activation of RAP1 requires cAMP-mediated activation of exchange factor activated by cAMP/RAPGEF3 whereas FSH activation of RAS and downstream signaling cascades involves multiple factors.

Gene expression profiles of cumulus cell oocyte complexes during ovulation reveal cumulus cells express neuronal and immune-related genes: does this expand their role in the ovulation process?

Ovulation is a complex process initiated by the preovulatory LH surge, characterized by cumulus oocyte complex (COC) expansion and completed by the release of a mature oocyte. Although many ovarian genes that impact ovulation have been identified, we hypothesized that genes selectively expressed in COCs would be overlooked by approaches using whole ovary or granulosa cell samples. RNA isolated from COCs collected from preovulatory follicles of equine chorionic gonadotropin (CG) primed mice and at selected times after human CG treatment was subjected to microarray analyses and results confirmed by RT-PCR analyses, Western blotting, and immunofluorescent studies.

Rhox: a new homeobox gene cluster.

Homeobox genes encode transcription factors notable for their ability to regulate embryogenesis. Here, we report the discovery of a cluster of 12 related homeobox genes on the X chromosome expressed in male and female reproductive tissues in adult mice. These reproductive homeobox on the X chromosome (Rhox) genes are expressed in a cell type-specific manner; several are hormonally regulated, and their expression pattern during postnatal testis development corresponds to their chromosomal position.

Pem homeobox gene promoter sequences that direct transcription in a Sertoli cell-specific, stage-specific, and androgen-dependent manner in the testis in vivo.

Although many genes are expressed selectively in Sertoli cells, regulatory sequences sufficient to drive Sertoli cell-specific expression in the postnatal and adult testis in vivo have not been identified. In the present study, we identified promoter sequences from the Pem homeobox gene that direct Sertoli cell-specific expression in an androgen-dependent and stage-specific manner. Immunohistochemical and RNA analysis demonstrated that 0.

Two novel human X-linked homeobox genes, hPEPP1 and hPEPP2, selectively expressed in the testis.

The PEPP genes are a recently described subfamily of mouse homeobox genes preferentially expressed in reproductive tissues. Pem, the founding member of the PEPP subfamily, has undergone rapid divergence due to positive selection, rendering the identification of its human orthologue difficult. Here we report the isolation and characterization of two human homeobox genes, hPEPP1 and hPEPP2, that are related to Pem and other PEPP family members.

Expression of the pem homeobox gene in Sertoli cells increases the frequency of adjacent germ cells with deoxyribonucleic acid strand breaks.

Pem is a member of the homeobox transcription factor family that is expressed in somatic cells in male and female reproductive tissues. In the murine testis, Pem is specifically expressed in Sertoli cells, where it is dramatically induced at the initiation of meiosis during the first wave of spermatogenesis and then later is restricted to stages IV-VIII of the seminiferous epithelial cycle. To study the function of Pem in Sertoli cells, we generated transgenic mice that express Pem in Sertoli cells during all stages of the seminiferous epithelial cycle.

Pem homeobox gene regulatory sequences that direct androgen-dependent developmentally regulated gene expression in different subregions of the epididymis.

The epididymis is a useful model system to understand the mechanisms that govern region-specific gene expression, as many gene products display spatially restricted expression within this organ. However, surprisingly little is known about how this regulation is achieved. Here, we report regulatory sequences from the Pem homeobox gene that drive expression in different subregions of the mouse epididymis in vivo.