Project description:Analysis of the coordinated transcriptional reponse to heat shock and ER stress mRNA profiles of NIH3T3 cells which stably expressing DD-sfGFP were generated by deep sequencing, in triplicate, using Illumina HiSeq. The samples were collected from indicated timepoints after exposed to either heat stress or ER stress.
Project description:We examined the stress response in Entamoeba histolytica trophozoites by comparing untreated log-phase HM-1:IMSS trophozoites to those subjected to heat shock at 42C for 1 hour. Keywords: stress reponse
Project description:We examined the stress response in Entamoeba histolytica trophozoites by comparing untreated log-phase HM-1:IMSS trophozoites to those subjected to heat shock at 42C for 1 hour. Keywords: stress reponse We compared two arrays from normal trophozoites to two arrays from trophozoites subjected to heat shock.
Project description:Organisms rely on coordinated stress responses to maintain cellular homeostasis. Perhaps the best-known example of multiple stress inputs converging onto a single response is the integrated stress response (ISR), which reduces global translation under various stressed conditions to reduce the protein folding burden of the cell. Similarly, most stress responses generally involve coordination of additional protein homeostasis (proteostasis) pathways, including increased expression of chaperones to refold proteins, as well as activation of clearance mechanisms, such as autophagy and the ubiquitin proteosome system. Our study investigates how heat stress can influence coordinated activation of both cytosolic and ER chaperones, exploring bidirectional cross talk between canonical activators of the cytosolic heat-shock response (HSR) and the unfolded protein response of the ER (UPRER). Using robust transcriptional reporters in the C. elegans model system, we explore a non-canonical activation of the UPRER under heat stress by the coordinated effects of XBP-1 and HSF-1. We further investigate inter tissue communications of stress whereby neuronal or glial activation of the UPRER can result in heterotypic enhancement of the HSR in peripheral and can increase thermotolerance. This work highlights the complex convergence of cellular stress responses, a phenomenon that may reflect a general strategy wherein localized stress can activate numerous proteostasis pathways to prevent whole cell and whole organism damage.
Project description:We investigated the root growth of several knockout mutants of heat shock protein family genes and found that heat stress response was compromised in these mutants compared to wild type plants. It suggested that heat shock protein genes including heat shock protein genes including HSP17s, HSP23s, HSP101, and HSFA2 proteins are deployed upon exposure to Cs for plant stress tolerance. Our study provided novel insights into the molecular events occurring in Cs-stressed plants.
Project description:Bioprinting holds the promise to revolutionize therapeutic development and healthcare; however, we still lack an in-depth understanding of how cells respond to stress experienced during the bioprinting process. Here, we assess at the molecular and cellular level the effects of bioprinting-induced stress on cell morphology, metabolism, and behavior using human umbilical vein endothelial cells. We demonstrate that mild preconditioning of the stress response in cells using heat shock before bioprinting helps cells to rapidly respond to bioprinting-associated stress, mitigating negative effects. We hypothesize this is in part mediated by the small heat shock protein 27 (Hsp27) which is known to play a role in stabilizing actin in the cytoskeleton. This results in restoration of cellular viability, morphology, metabolism, and function, including vascularization. Our study outlines an easy-to-implement strategy to improve cell viability following bioprinting, facilitating the real-life application of bioprinting.
Project description:Whole-genome analysis of heat shock factor binding sites in Drosophila melanogaster. Heat shock factor IP DNA or Mock IP DNA from heat shocked Kc 167 cells compared to whole cell extract on Agilent 2x244k tiling arrays.
Project description:Heat shock response (HSR) is a cellular defense mechanism against various stresses. Both heat shock and proteasome inhibitor MG132 cause the induction of heat shock proteins, a distinct feature of HSR. To better understand the molecular basis of HSR, we subjected the mouse fibrosarcoma cell line, RIF-1, and its thermotolerant variant, TR-RIF-1 cells, to heat shock and MG132. We compared mRNA expressions using microarray analysis during recovery after heat shock and MG132 treatment. This study led us to group the 3,245 up-regulated genes by heat shock and MG132 into three families: genes regulated 1) by both heat shock and MG132 (e.g. chaperones); 2) by heat shock (e.g. DNA-binding proteins including histones); and 3) by MG132 (e.g. innate immunity and defense-related molecules).
Project description:Cells respond to many different types of stresses by overhauling gene expression patterns, both at the transcriptional and translational level. Under heat stress, global transcription and translation are inhibited, while the expression of chaperone proteins are preferentially favored. As the direct link between mRNA transcription and protein translation, tRNA expression is intricately regulated during the stress response. Despite extensive research into the heat shock response (HSR), the regulation of tRNA expression by RNA Polymerase III (Pol III) transcription has yet to be fully elucidated in mammalian cells. Here, we examine the regulation of Pol III transcription during different stages of heat shock stress in mouse embryonic stem cells (mESCs). We observe that global transcription of tRNAs is downregulated after 30 minutes of heat shock, followed by an overall increase in tRNA transcription after 60 minutes of heat shock. This effect is more evident in tRNAs, though other RNA Pol III gene targets are also similarly affected. Notably, we show that the down-regulation at 30 minutes of heat shock is independent of HSF1, the master transcription factor of the HSR, but that the subsequent increase in expression at 60 minutes requires HSF1. Taken together, these results demonstrate an adaptive RNA Pol III response to heat stress, and an intricate relationship between the canonical HSR and tRNA expression.