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Author(s): Jeremy Cohen [sup.1] [sup.2] [sup.3] [sup.4], Antje Blumenthal [sup.5], Gabriel Cuellar-Partida [sup.5], David M. Evans [sup.5] [sup.6], Simon Finfer [sup.1] [sup.7] [sup.8] [sup.9], Qiang Li [sup.1], Johanna Ljungberg [sup.5], [...], Purpose To determine if adrenocortical gene expression is associated with clinical outcomes or response to corticosteroid treatment in septic shock. Methods A pre-specified nested cohort study of a randomised controlled trial of hydrocortisone compared to placebo in septic shock. Blood was collected for RNAseq analysis prior to treatment with hydrocortisone or placebo. The expression of adrenocortical candidate genes related to pituitary releasing hormones, mineralocorticoid and glucocorticoid receptors, intracellular glucocorticoid metabolism and transport proteins was measured. Results From May 2014 to April 2017, 671 patients were enrolled in the nested cohort study, from which 494 samples were available for analysis. We found no evidence of an association between candidate gene expression levels and either 90-day mortality, 28-day mortality or time to shock reversal. We observed evidence of a significant interaction between expression and treatment group for time to shock reversal in two genes; GLCCI1 (HR 3.81, 95%CI 0.57-25.47 vs. HR 0.64, 95%CI 0.13-3.07 for hydrocortisone and placebo respectively, p for interaction 0.008) and BHSD1 (HR 0.55, 95%CI 0.28-1.09 vs. HR 1.32 95%CI 0.67-2.60, p for interaction 0.01). Conclusions In patients with septic shock, there is no association between adrenocortical candidate gene expression and mortality. Patients with higher expression of GLCCI1 who received hydrocortisone achieved shock resolution faster than those receiving placebo; conversely, patients who had higher expression of BHSD1 who received hydrocortisone achieved shock resolution slower than those who received placebo. Variation in gene expression may be a mechanism for heterogeneity of treatment response to corticosteroids in septic shock.

Misfolding of exportable proteins can trigger endocrinopathies. For example, misfolding of insulin can result in autosomal dominant mutant INS gene--induced diabetes of youth, and misfolding of thyroglobulin can result in [...]

HATs and HDACs target histones and non-histone proteins (1-4) and regulate chromosome dynamics. They also influence the DNA damage response through acetylation of key DNA repair and checkpoint proteins (2). [...], Protein acetylation is mediated by histone acetyltransferases (HATs) and deacetylases (HDACs), which influence chromatin dynamics, protein turnover and the DNA damage response. ATM and ATR mediate DNA damage checkpoints by sensing double-strand breaks and single-strand-DNA-RFA nucleofilaments, respectively. However, it is unclear how acetylation modulates the DNA damage response. Here we show that HDAC inhibition/ablation specifically counteracts yeast Mecl (orthologue of human ATR) activation, double-strand-break processing and single-strand-DNA-RFA nucleofilament formation. Moreover, the recombination protein Sae2 (human CtIP) is acetylated and degraded after HDAC inhibition. Two HDACs, Hda1 and Rpd3, and one HAT, Gcn5, have key roles in these processes. We also find that HDAC inhibition triggers Sae2 degradation by promoting autophagy that affects the DNA damage sensitivity of hda1 and rpd3 mutants. Rapamycin, which stimulates autophagy by inhibiting Tor, also causes Sae2 degradation. We propose that Rpd3, Hda1 and Gcn5 control chromosome stability by coordinating the ATR checkpoint and double-strand-break processing with autophagy.

Author(s): Laura Pontano Vaites; J. Wade Harper Neurodegenerative diseases are often associated with genetic mutations that cause repetition of short sequences of nucleotides. In the disorders amyotrophic lateral sclerosis (ALS, [...]

Lysine histone methylation is one of the most robust epigenetic marks and is essential for the regulation of multiple cellular processes. The methylation of Lys4 of histone H3 seems to [...]

Molecular Cloning and Expression of a Complementary DNA for Inositol 1,4,5-Trisphosphate 3-Kinase INOSITOL 1,4,5-TRISPHOSPHATE [I(1,4,5)[P.sub.3]], product of phospholipase C activity on phosphatidylinositol 4,5-bisphosphate, is metabolized through two separate pathways: sequential [...]

Key Words chromosome partitioning, plasmid partitioning, ParA homolog, ParB homolog, Sine protein, MukFEB complex, oriC * Abstract Plasmid-encoded partition genes determine the dynamic localization of plasmid molecules from the mid-cell [...]

Replication Protein A (RPA) is a heterotrimeric complex in all eukaryotes that is essential for DNA replication, repair/recombination, and cell cycle regulation. In response to DNA damage, the N-terminus (NT) of the human Rpa2 subunit becomes hyper-phosphorylated by several checkpoint kinases. Previously, we demonstrated in the budding yeast Saccharomyces cerevisiae that yeast Rpa2 NT phosphorylation is difficult to detect under genotoxic conditions, yet it is vital for the damage response. To overcome this, we generated chimeric yeast Rpa2 proteins containing the human NT, and previously showed that the chimeric Rpa2 in yeast is hyper-phosphorylated in a manner nearly indistinguishable from that in human cells. In human cells, phosphorylation of human Rpa2 NT at specific sites is not only damage-dependent, but also interdependent in that phosphorylation of one site depends on previous phosphorylation of other sites within the NT. To examine this in yeast, we generated and utilized individual non-phosphorylatable site mutants. In yeast cells, phosphorylation at one site does not depend on phosphorylation at different phospho-sites within the NT. Furthermore, we have found that different types of damage can affect phosphorylation of the human Rpa2 NT differently in yeast. Identification and characterization of phosphorylation of both the yeast (native) and 'humanized' yeast Rpa2 allows us to gain an understanding of conserved properties/functions between the two systems., Barbara L. Senger (U) and Stuart J. Haring Chemistry and Biochemistry, North Dakota State University, Fargo, ND Support: This work was supported by award NSF-CAREER-1253723 from the National Science Foundation [...]

A number of secreted proteins are known to contribute to virulence in Pseudomonas aeruginosa (Pa). We are attempting to understand the function and interaction of several of these proteins namely [...]