To identify biologically functional regions in the product of the Drosophila melanogaster gene Kruppel, we cloned the Kruppel homolog from Drosophila virilis. Both the previously identified amino (N)-terminal repression region and the DNA-binding region of the D. virilis Kruppel protein are greater than 96% identical to those of the D. melanogaster Kruppel protein, demonstrating a selective pre...

The biogenesis of ribosomes is coordinated with cell growth and proliferation. Distortion of the coordinated synthesis of ribosomal components affects not only ribosome formation, but also cell fate. However, the connection between ribosome biogenesis and cell fate is not well understood. To establish a model system for inquiries into these processes, we systematically analyzed cell cycle progr...

Short-range transcriptional repressors are locally acting factors that play important roles in developmental gene expression in Drosophila. To effect repression, Knirps and other short-range repressors bind the CtBP corepressor, but these repressors also function via CtBP-independent pathways. Possible mechanistic differences between CtBP-dependent and -independent repression activities are poo...

Strains were constructed that contain mutational alterations affecting two distinct functional domains within the araC gene protein. The araCi (catabolite repression insensitivity) and araCh (catabolite repression hypersensitivity) mutations were used to alter the catabolite repression sensitivity domain, and mutation to D-fucose resistance was used to alter the inducer binding domain. araCh, D...

The effects of induction and of transient and catabolite repression on lac-specific RNA in cells of Escherichia coli were investigated. The rate of Zac-specific RNA synthesis increases linearly for 3 min after induction and then becomes constant. The accumulation of RNA complementary to the promoter proximal tat 2 gene begins before accumulation of RNA complementary to the promoter distal lac Y...

The E2F4 and E2F5 proteins specifically associate with the Rb-related p130 protein in quiescent cells to repress transcription of various genes encoding proteins important for cell growth. A series of reports has provided evidence that Rb-mediated repression involves both histone deacetylase (HDAC)-dependent and HDAC-independent events. Our previous results suggest that one such mechanism for R...

nAture methods | ADVANCE ONLINE PUBLICATION | We tested whether transcription activator–like effectors (tAles) could mediate repression and activation of endogenous enhancers in the Drosophila genome. tAle repressors (tAlers) targeting each of the five even-skipped (eve) stripe enhancers generated repression specifically of the focal stripes. tAle activators (tAleAs) targeting the eve promoter ...

Sin3 and Rpd3 negatively regulate a diverse set of yeast genes. A mouse Sin3-related protein is a transcriptional corepressor, and a human Rpd3 homolog is a histone deacetylase. Here, we show that Sin3 and Rpd3 are specifically required for transcriptional repression by Ume6, a DNA-binding protein that regulates genes involved in meiosis. A short region of Ume6 is sufficient to repress transcri...

The effects of induction and of transient and catabolite repression on lac-specific RNA in cells of Escherichia coli were investigated. The rate of Zac-specific RNA synthesis increases linearly for 3 min after induction and then becomes constant. The accumulation of RNA complementary to the promoter proximal tat 2 gene begins before accumulation of RNA complementary to the promoter distal lac Y...

We tested the effect of systematic destruction of all three lac operators of the chromosomal lac operon of Escherichia coli on repression by Lac repressor. Absence of just one 'pseudo-operator' O2 or O3 decreases repression by wild-type tetrameric Lac repressor approximately 2- to 3-fold; absence of both 'pseudo-operators' decreases repression greater than 50-fold. O1 alone represses under thes...