Project description:Analysis of LBNF1 rat testes from controls, containing both somatic and all germ cell types and from irradiated rats in which all cells germ cells except type A spermatgogonia are eliminated. Results provide insight into distinguishing germ and somatic cell genes and identification of somatic cell genes that are upregulated after irradiation.
Project description:In order to establish a rat embryonic stem cell transcriptome, mRNA from rESC cell line DAc8, the first male germline competent rat ESC line to be described and the first to be used to generate a knockout rat model was characterized using RNA sequencing (RNA-seq) analysis.
Project description:A series of two color gene expression profiles obtained using Agilent 44K expression microarrays was used to examine sex-dependent and growth hormone-dependent differences in gene expression in rat liver. This series is comprised of pools of RNA prepared from untreated male and female rat liver, hypophysectomized (‘Hypox’) male and female rat liver, and from livers of Hypox male rats treated with either a single injection of growth hormone and then killed 30, 60, or 90 min later, or from livers of Hypox male rats treated with two growth hormone injections spaced 3 or 4 hr apart and killed 30 min after the second injection. The pools were paired to generate the following 6 direct microarray comparisons: 1) untreated male liver vs. untreated female liver; 2) Hypox male liver vs. untreated male liver; 3) Hypox female liver vs. untreated female liver; 4) Hypox male liver vs. Hypox female liver; 5) Hypox male liver + 1 growth hormone injection vs. Hypox male liver; and 6) Hypox male liver + 2 growth hormone injections vs. Hypox male liver. A comparison of untreated male liver and untreated female liver liver gene expression profiles showed that of the genes that showed significant expression differences in at least one of the 6 data sets, 25% were sex-specific. Moreover, sex specificity was lost for 88% of the male-specific genes and 94% of the female-specific genes following hypophysectomy. 25-31% of the sex-specific genes whose expression is altered by hypophysectomy responded to short-term growth hormone treatment in hypox male liver. 18-19% of the sex-specific genes whose expression decreased following hypophysectomy were up-regulated after either one or two growth hormone injections. Finally, growth hormone suppressed 24-36% of the sex-specific genes whose expression was up-regulated following hypophysectomy, indicating that growth hormone acts via both positive and negative regulatory mechanisms to establish and maintain the sex specificity of liver gene expression. For full details, see V. Wauthier and D.J. Waxman, Molecular Endocrinology (2008)
Project description:Although numerous miRNAs have been identified in the testis, their roles in regulating the highly specific events that occur in the different germ cell types throughout spermatogenesis remain largely unknown. Furthermore, whether male germ cell miRNA expression is altered in response to or as a consequence of exposure to a toxic agent is unknown. Here we examine miRNA expression profiles in pachytene spermatocytes and round spermatids obtained from control rats and from rats treated with a chronic low dose of cyclophosphamide, a male germ cell toxicant. We observed that pachytene spermatocytes and round spermatids display vastly different miRNA expression profiles, reflecting their different developmental stages and possibly influencing the cellular response to toxic insult. Chronic low dose cyclophosphamide treatment altered the miRNA profiles in both pachytene spermatocytes and round spermatids. Target prediction analyses revealed that miRNAs altered by cyclophosphamide treatment may be involved in the response to cellular stress and damage. However, many are also involved in processes that are crucial for proper germ cell development. This study suggests that pachytene spermatocytes and round spermatids display distinct miRNA profiles that can be altered by cyclophosphamide treatment. The observed changes may be part of a response and repair mechanism to cyclophosphamide-induced damage or a dysregulation that disrupts normal germ cell development.
Project description:This is a study to explore the transcriptional changes after Adjudin treatment in adult rat testes at three time points (control, 8 hour and 4 day). Adjudin, [1-(2,4-dichlorobenzyl)-1H-indazole-3-carbohydrazide], is a potential male contraceptive that targets the Sertoli-germ cell interface and causes germ cell depletion from the seminiferous epithelium. Adjudin has been proved to be a useful model to study the mechanisms that regulate junction restructuring in the testis. Experiment Overall Design: Sprague-Dawley rats treated with a single dose of Adjudin at 50 mg/kg b.w. by gavage and terminated after 8 hours (n=2) and 4 days (n=3). Testes from Adjudin-treated rats and untreated (control, n=3) rats were harvested and total RNA were prepared. Standard Affymetrix genechip procedures were followed for the subsequent experiments. Data were analysed in MAS 5.0 and GeneSpring 7.2.