Endotoxin tolerance occurs to protect the organism from hyperactivation of innate immune responses, primarily mediated by macrophages. Regulation of endotoxin tolerance occurs at multiple levels of cell responses and requires significant changes in gene expression. In the process of macrophage activation, induced expression of microRNA (miR)-155 and miR-146a contributes to the regulation of the...

Ig class switch recombination (CSR) requires expression of activation-induced cytidine deaminase (AID) and transcription through target switch (S) regions. Here we show that knockdown of the histone chaperone facilitates chromatin transcription (FACT) completely inhibited S region cleavage and CSR in IgA-switch-inducible CH12F3-2A B cells. FACT knockdown did not reduce AID or S region transcrip...

The exosome complex functions in RNA metabolism and transcriptional gene silencing. Here, we report that mutations of two Arabidopsis genes encoding nuclear exosome components AtRRP6L1 and AtRRP6L2, cause de-repression of the main flowering repressor FLOWERING LOCUS C (FLC) and thus delay flowering in early-flowering Arabidopsis ecotypes. AtRRP6L mutations affect the expression of known FLC reg...

Background Placentation shares many analogues with the development of tumors such as rapid proliferation, invasiveness, gene expression profiles especially the expression of tumor suppressor genes, oncogenes and matrixmetallo proteinases (MMPs). Thus, a placenta has been described as a pseudomalignant tissue. However, placentation is tightly regulated and any deregulation of this pseudomalignan...

Histone lysine methylation is a central modification to mark functionally distinct chromatin regions. In particular, H3-K9 trimethylation has emerged as a hallmark of pericentric heterochromatin in mammals. Here we show that H4-K20 trimethylation is also focally enriched at pericentric heterochromatin. Intriguingly, H3-K9 trimethylation by the Suv39h HMTases is required for the induction of H4-...

Warfarin dose requirements have been associated with 2 main haplotypes in VKORC1, but the responsible polymorphisms remain unknown. To search for regulatory polymorphisms, we measured allelic mRNA expression of VKORC1 in human liver, heart, and B lymphocytes. The observed 2-fold allelic mRNA expression imbalance narrowed possible candidate SNPs to -1639G>A and 1173C<T. This genotype effect was ...

Trimethylation of lysine 4 of histone H3 occurs at the 5' end of active genes and is catalyzed by Set1 in Saccharomyces cerevisiae. Trimethylation requires histone H2B ubiquitylation and the PAF1 complex, which are linked to transcription elongation, but how they activate Set1 is not known. Set1 also bears several conserved domains with uncharacterized contributions to activity. Here, we isolat...