B cell to plasma cell maturation is marked by the loss of MHC class II expression. This loss is due to the silencing of the MHC class II transcriptional coactivator CIITA. In this study, experiments to identify the molecular mechanism responsible for CIITA silencing were conducted. CIITA is expressed from four promoters in humans, of which promoter III (pIII) controls the majority of B cell-med...

Acetylation is one of the most important post-translational modification of proteins determining the structure, function and intracellular localization that plays an important role in the signal transduction pathways related to diverse cell functions, both during unstimulated and stress conditions. Protein acetylation in cells is regulated by a co-ordinated action of histone acetyl transferases...

NOK is a potent oncogene that can transform normal cells to cancer cells. We hypothesized that NOK might impact cancer cell metabolism and histone acetylation. We show that NOK localizes in the mitochondria, and while it minimally impacts tricarboxylic acid (TCA) cycle, it markedly inhibits the process of electron transport and oxidative phosphorylation processes and dramatically enhances aerob...

Epigenetic modification such as DNA methylation and histone acetylation plays essential roles in many aspects of cellular function and development of animals. There is an increasing amounts of evidence for dynamic changes in the histone acetylation of specific gene segments, but little attempt was made to examine global pattern changes in the histone acetylation in developing nervous system. In...

Epigenetic mechanisms have been widely implicated in synaptic plasticity and in memory consolidation, yet little is known about the role of epigenetic mechanisms in memory reconsolidation processes. In the present study, we systematically examine the role of histone acetylation and DNA methylation in the reconsolidation of an amygdala-dependent Pavlovian fear memory. We first show that the acet...

While chromatin modifications can offer a useful readout for enhancer activities, it is less clear whether these modification marks are a cause or consequence of transcription factor occupancy and enhancer activation. We have examined in details the temporal events of acetyltransferase associations and histone acetylations at different regulatory regions of the Myod1 locus. Our studies demonstr...

Posttranslational modifications (PTMs) of histone proteins, such as acetylation, methylation, phosphorylation, and ubiquitylation, play essential roles in regulating chromatin dynamics. Combinations of different modifications on the histone proteins, termed 'histone code' in many cases, extend the information potential of the genetic code by regulating DNA at the epigenetic level. Many PTMs occ...

The maize C(4)-Pepc gene is expressed in an organ- and cell-type-specific manner, inducible by light and modulated by nutrient availability and the metabolic state of the cell. We studied the contribution of histone acetylation at five lysine residues to the integration of these signals into a graduated promoter response. In roots and coleoptiles, where the gene is constitutively inactive, thre...

Histone chaperones are thought to be important for maintaining the physiological activity of histones; however, their exact roles are not fully understood. The physiological function of template activating factor (TAF)-I, one of the histone chaperones, also remains unclear; however, its biochemical properties have been well studied. By performing microarray analyses, we found that TAF-I stimula...

We previously showed that Arabidopsis thaliana histone acetyltransferase TAF1/HAF2 is required for the light regulation of growth and gene expression, and we show here that histone acetyltransferase GCN5 and histone deacetylase HD1/HDA19 are also involved in such regulation. Mutation of GCN5 resulted in a long-hypocotyl phenotype and reduced light-inducible gene expression, whereas mutation of ...