Purnima Bhargava

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To study nucleosome mobility and positioning, the R3 lac repressor was used with an adenosine triphosphate (ATP)-dependent chromatin assembly system to establish the positioning of five nucleosomes, with one nucleosome located between two R3 lac operators. When R3 protein was dissociated from DNA with isopropyl beta-D-thiogalactopyranoside, the R3-induced(More)
FACT complex is involved in elongation and ensures fidelity in the initiation step of transcription by RNA polymerase (pol) II. Histone variant H2A.Z is found in nucleosomes at the 5'-end of many genes. We report here H2A.Z-chaperone activity of the yeast FACT complex on the short, nucleosome-free, non-coding, pol III-transcribed yeast tRNA genes. On a(More)
Recent research suggests that minor changes in the primary sequence of the conserved histones may become major determinants for the chromatin structure regulating gene expression and other DNA-related processes. An analysis of the involvement of different core histone variants in different nuclear processes and the structure of different variant nucleosome(More)
Binding characteristics of yeast TATA-binding protein (yTBP) over five oligomers having different TATA variants and lacking a UASGAL, showed that TATA-binding protein (TBP)-TATA complex gets stabilized in the presence of the acidic activator GAL4-VP16. Activator also greatly suppressed the non-specific TBP-DNA complex formation. The effects were more(More)
Olfactory bulbs (OBs) are one of the few brain areas, which show active neurogenesis and neuronal migration processes in adult rats. We constructed a proteome map of the 21 days old rat OBs and identified total 196 proteins, out of which 76 proteins were not reported earlier from rat brain. This includes 24 neuronal activity-specific proteins present at(More)
RNA polymerase (pol) III transcribes a unique class of genes with intra-genic promoters and high transcriptional activity. The major contributors to the pol III transcriptome, tRNAs genes are found scattered on all chromosomes of yeast. A prototype tDNA of <150 bp length, is generally considered nucleosome-free while some pol III-transcribed genes have been(More)
Dimerization is proposed to be a regulatory mechanism for TATA-binding protein (TBP) activity both in vitro and in vivo. The reversible dimer-monomer transition of TBP is influenced by the buffer conditions in vitro. Using in vitro chemical cross-linking, we found yeast TBP (yTBP) to be largely monomeric in the presence of the divalent cation Mg2+, even at(More)
Cerebellum is an important brain region involved in motor, cognition, learning and memory functions. Proteome mapping of the 21 days old rat cerebellum identified total 285 proteins, out of which 76 proteins were not reported earlier from rat brain. This includes 49 neuronal activity-specific proteins, 7 of which are reported for the first time from the(More)
Chromosomes architecture is viewed as a key component of gene regulation, but principles of chromosomal folding remain elusive. Here we used high-throughput live cell microscopy to characterize the conformation and dynamics of the longest chromosome of Saccharomyces cerevisiae (XII). Chromosome XII carries the ribosomal DNA (rDNA) that defines the(More)
The genes transcribed by RNA polymerase III (Pol III) generally have intragenic promoter elements. One of them, the yeast U6 snRNA (SNR6) gene is activated in vitro by a positioned nucleosome between its intragenic box A and extragenic, downstream box B separated by approximately 200 bp. We demonstrate here that the in vivo chromatin structure of the gene(More)