Project description:To determine the complement of Ume6-dependent genes expressed during mitosis and/or meiosis in budding yeast we compared wild-type and<br>ume6 deletion strains using Yeast 2.0 high density oligonucleotide microarrays (GeneChips). Samples were analysed from cells growing in rich medium with fermentable (glucose) and non-fermentable (acetate) carbon sources and from cells undergoing meiosis and spore formation in sporulation medium. Expression data were combined with data from a genome-wide Ume6 DNA binding assay and Ume6-target site prediction to identify the most likely direct target genes of Ume6.
Project description:We wanted to study regulation of gene regulation by sba1 (ortholog of mammalian p23) in yeast. sba1/p23 binds to Hsp90 and acts as a co-chaperone. We have a small molecule, radicicol, an analog of geldanamycin to inhibit the binding of p23 to Hsp90. Consequently, we have analyzed the gene expression profile in 4 conditions, wt, delta-sba1; and when Hsp90 function is impaired, that is, wt and delta-sba1 treated with radicicol.
Project description:To study the role of the testis determining gene Sox9 after testis induction, conditional inactivation of Sox9 was achieved with the help of an AMH-Cre line. Mutant mice are fertile up to about 3 months of age, becoming sterile afterwards. Expression profiles should help to reveal the underlying cause.
Project description:Identification of gene expression patterns that correlate with distinct stages of male germ cell development using biopsies from men with highly defined and homogenous testicular pathologies based on the Johnsen score procedure. The Johnsen score procedure is a classical histopathological scoring procedure that classifies the germ cell composition from different stages of spermatogenic impairment.
Project description:To study a possible redundant role of mouse Sox8 and Sox9 after testis induction we generated double mutants by AMH-Cre conditional inactivation of Sox9 in a Sox8-/- background. Double mutants arrest spermatogenesis in early pubescence. We performed expression profiling to explore causes. AMH-Cre/+;Sox9flox/flox;Sox8-/- is a conditional homozygous knockout of SOX9 in a sox8-/- background, using an AMH-CRE line where the CRE recombinase is expressed under the promoter region of the human AMH gene in Sertoli cells starting at E13.5. The specific cross was between males of the genotype +/+;Sox9flox/flox;Sox8-/- and females of the genotype AMH-Cre/+;Sox9flox/flox;Sox8+/-.
Project description:Deregulation of translational control is frequently implicated in the establishment and maintenance of the cancer phenotype. Anti-cancer drugs targeting protein synthesis are confronted by the problem that genes can exploit alternative translational mechanisms. To better understand the molecular mechanism behind these alternative translational routes we have exploited an ex-vivo assay that follows a competitive re-recruitment of cellular mRNAs onto polysomes in cells treated or not with rapamycin.
Project description:Found PAR bZip target genes. The loss of circadian PAR bZip transcription factors results in epilepsy, DBP (albumin D-site-binding protein), HLF (hepatic leukemia factor), and TEF (thyrotroph embryonic factor) are the three members of the PAR bZip (proline and acidic amino acid-rich basic leucine zipper) transcription factor family. All three of these transcriptional regulatory proteins accumulate with robust circadian rhythms in tissues with high amplitudes of clock gene expression, such as the suprachiasmatic nucleus (SCN) and the liver. However, they are expressed at nearly invariable levels in most brain regions, in which clock gene expression only cycles with low amplitude. Here we show that mice deficient for all three PAR bZip proteins are highly susceptible to generalized spontaneous and audiogenic epilepsies that frequently are lethal. Transcriptome profiling revealed pyridoxal kinase (Pdxk) as a target gene of PAR bZip proteins in both liver and brain. Pyridoxal kinase converts vitamin B6 derivatives into pyridoxal phosphate (PLP), the coenzyme of many enzymes involved in amino acid and neurotransmitter metabolism. PAR bZip-deficient mice show decreased brain levels of PLP, serotonin, and dopamine, and such changes have previously been reported to cause epilepsies in other systems. Hence, the expression of some clock-controlled genes, such as Pdxk, may have to remain within narrow limits in the brain. This could explain why the circadian oscillator has evolved to generate only low-amplitude cycles in most brain regions.; find REV-ERB ALPHA target genes