NELF and DSIF collaborate to inhibit elongation by RNA polymerase IIa in extracts from human cells. A multifaceted approach was taken investigate the potential role of these factors promoter proximal pausing on hsp70 gene Drosophila . Immunodepletion a nuclear extract reduced level that paused region Depletion one subunit salivary glands using interference also polymerase. In vivo protein–DNA cross-linking showed associate with before heat shock. Immunofluorescence analysis polytene...

In both Drosophila and vertebrates, spatially restricted expression of HOX genes is controlled by the Polycomb group (PcG) repressors. Here we characterize a novel PcG gene, Suppressor zeste 12 (Su(z)12). Su(z)12 mutants exhibit very strong homeotic transformations function required throughout development to maintain repressed state genes. Unlike most other mutations, mutations are suppressors position-effect variegation (PEV), suggesting that also functions in heterochromatin-mediated...

Chromosomal instability, which involves the deletion and duplication of chromosomes or chromosome parts, is a common feature cancers, deficiency screens are commonly used to detect genes involved in various biological pathways. However, despite their importance, effects deficiencies, duplications, losses on regulation whole large domains largely unknown. Therefore, explore these effects, we examined expression patterns several Drosophila hemizygotes hemizygote using microarrays. The results...

Chromosome-specific gene regulation is known thus far only as a mechanism to equalize the transcriptional activity of single male X chromosome with that two female chromosomes. In Drosophila melanogaster , complex including five Male-Specific Lethal (MSL) proteins, “paints” chromosome, mediating its hypertranscription. Here, molecular cloning Painting fourth ( Pof ), we describe previously uncharacterized encoding chromosome-specific protein in . Unlike MSL POF paints an autosome, Chromosome...

Heterochromatin protein 1 (HP1) proteins, recognized readers of the heterochromatin mark methylation histone H3 lysine 9 (H3K9me), are important regulators heterochromatin-mediated gene silencing and chromosome structure. In Drosophila melanogaster three methyl transferases (HKMTs) associated with H3K9: Su(var)3-9, Setdb1, G9a. To probe dependence HP1a binding on H3K9me, its these HKMTs, division labor between we have examined correlations H3K9me patterns in wild type null mutants HKMTs. We...

Heterochromatin protein 1a (HP1a) is a chromatin-associated important for the formation and maintenance of heterochromatin. In Drosophila , two histone methyltransferases SETDB1 Su(var)3-9 mediate H3K9 methylation marks that initiates establishment spreading HP1a-enriched chromatin. Although HP1a generally regarded as factor represses gene transcription, several reports have linked binding to active genes, in some cases, it has been shown stimulate transcriptional activity. To clarify...

Thioredoxins are proteins that have thiol-reducing activity and a characteristic conserved active site (WCGPC). They several documented functions, e.g. roles in defences against oxidative stress as electron donors for ribonucleotide-reductase. In Drosophila melanogaster there three "classical" thioredoxins with the site: deadhead, ThioredoxinT Thioredoxin-2. Here, we report creation of null-mutations Thioredoxin-2 (Trx-2) gene. Characterization two Trx-2 mutants indicated affects lifespan D....

Mammalian G9a is a histone H3 Lys-9 (H3–K9) methyltransferase localized in euchromatin and acts as co-regulator for specific transcription factors. required proper development mammals g9a−/g9a− mice show growth retardation early lethality. Here we describe the cloning, biochemical genetical analyses of Drosophila homolog dG9a. We that dG9a shares structural organization mammalian G9a, it multi-catalytic with specificity not only lysines 9 27 on but also H4. Surprisingly, H4–K20 residue...

Two specific chromosome-targeting and gene regulatory systems are present in Drosophila melanogaster. The male X chromosome is targeted by the male-specific lethal complex believed to mediate 2-fold up-regulation of X-linked genes, highly heterochromatic fourth specifically Painting Fourth (POF) protein, which, together with heterochromatin protein 1 (HP1), modulates expression level genes on chromosome. Here we use chromatin immunoprecipitation tiling microarray analysis map POF HP1 S2...

Mammalian sex chromosomes evolved from the degeneration of one homolog a pair ancestral autosomes, proto-Y. This resulted in gene dose imbalance that is believed to be restored (partially or fully) through upregulation expression single active X-chromosome both sexes by dosage compensatory mechanism. We analyzed multiple genome-wide RNA stability data sets and found significantly longer average half-lives for transcripts than autosomal various human cell lines, male female, mice. Analysis...

Regulation of chromatin through histone acetylation is an important step in gene expression. The Gcn5 acetyltransferase part protein complexes, e.g., the SAGA complex, that interact with transcriptional activators, targeting enzyme to specific promoters and assisting recruitment basal RNA polymerase transcription machinery. Ada2 directly binds stimulates its catalytic activity. Drosophila contains two proteins, Ada2a (dAda2a) dAda2b. We have generated flies lack dAda2b, which a SAGA-like...

Painting of fourth (POF) is a chromosome-specific protein in Drosophila and represents the first example an autosome-specific protein. POF binds to chromosome 4 melanogaster , initiating at proximal region, followed by spreading dependent on 4-specific sequences or structures. Chromosome-specific gene regulation known thus far only as mechanism equalize transcriptional activity single male X with that two female chromosomes. In complex including male-specific lethal proteins, “paints”...

Variation in the number of individual chromosomes (chromosomal aneuploidy) or chromosome segments (segmental is associated with developmental abnormalities and reduced fitness all species examined; it leading cause miscarriages mental retardation a hallmark cancer. However, despite their documented importance disease, effects aneuploidies on transcriptome remain largely unknown. We have examined expression seven heterozygous chromosomal deficiencies, both singly pairwise combinations,...

In Drosophila, two chromosome-wide compensatory systems have been characterized: the dosage compensation system that acts on male X chromosome and chromosome-specific regulation of genes located heterochromatic fourth chromosome. Dosage in Drosophila is accomplished by hypertranscription single mediated male-specific lethal (MSL) complex. The mechanism this suggested to involve enhanced transcriptional elongation MSL complex, while painting (POF) protein has remained elusive. Here, we show...

Long non-coding RNAs contribute to dosage compensation in both mammals and Drosophila by inducing changes the chromatin structure of X-chromosome. In melanogaster, roX1 roX2 are long that together with proteins form male-specific lethal (MSL) complex, which coats entire male X-chromosome mediates increasing its transcriptional output. Studies on polytene chromosomes have demonstrated when absent, MSL-complex becomes less abundant is relocated chromocenter 4th chromosome. Here we address role...

Car parking has been, and still is, a growing problem, with increasing vehicle sizes in the luxury segment as well sport-utility vehicles. This is especially true when bearing mind confined spaces lots cities. While damage during generally does not cause any injury to passengers, it costly annoying. Park assist systems are by no means new on market, since passive which provide longitudinal guidance using ultrasonic distance sensors have been available market for number of years. The system...

In Drosophila melanogaster, the male-specific lethal (MSL) complex plays a key role in dosage compensation by stimulating expression of male X-chromosome genes. It consists MSL proteins and two long noncoding RNAs, roX1 roX2, that are required for spreading on chromosome redundant sense loss either does not affect viability. However, despite rapid evolution, both roX species present diverse Drosophilidae species, raising doubts about their full functional redundancy. Thus, we have...

Abstract This paper considers the nonlinear interaction between three waves in a warm magnetized twocomponent plasma. A general formalism is developed within simple macroscopic theory order to treat propagating arbitrary directions. Some results of previous papers are generalized and discussed.