Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Expression data from primary hepatocytes knocking down or overexpressing IRE1a

ABSTRACT: The ER-resident protein kinase/endoribonuclease IRE1 is activated through trans-autophosphorylation in response to protein folding overload in the ER lumen and maintains ER homeostasis by triggering a key branch of the unfolded protein response. Here we show that mammalian IRE1a in liver cells is also phosphorylated by a kinase other than itself in response to metabolic stimuli. Glucagon stimulated protein kinase PKA, which in turn phosphorylated IRE1a at Ser724, a highly conserved site within the kinase activation domain. Blocking Ser724 phosphorylation impaired the ability of IRE1a to augment the upregulation by glucagon signaling of the expression of gluconeogenic genes. Moreover, hepatic IRE1a was highly phosphorylated at Ser724 by PKA in mice with obesity, and silencing hepatic IRE1a markedly reduced hyperglycemia and glucose intolerance. Hence, these results suggest that IRE1a integrates signals from both the ER lumen and the cytoplasm in the liver and is coupled to the glucagon signaling in the regulation of glucose metabolism. We used DNA microarray to analyze the transcriptomic change upon IRE1a overexpression or IRE1a depletion in primary hepatocytes, to study the changes related to IRE1a Primary hepatocytes were infected with the desired adenoviruses (Ad-EGFP, Ad-WT, Ad-S724A, Ad-shCON, Ad-shIRE1a#2) or treated with glucagon. Total cellular RNA was isolated with TRIzol (Invitrogen) and subjected to analysis by Affymetrix Mouse Genome 430 2.0 Arrays. Three experiments were independently conducted.

ORGANISM(S): Mus musculus

SUBMITTER: Ting Mao

PROVIDER: E-GEOD-31638 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:INS1-EGFP-L10a stable cell lines were induced with Doxycycline (Dox) for 24 hours, then either untreated or treated for 30 minutes with 1uM Thapsigargin to induce ER stress. Total RNA was purified with Trizol, and RIP RNA samples were extracted by immunoaffinity purification using an EGFP antibody We aimed to determine which genes are enriched under ER stress at the polyribosomal level. To do this we compared expression profiles of Total RNA with and without ER stress, and Immunoaffinity purified RNA (RIP) with and without ER stress. Microarray results of INS-1 EGFP-L10a cells either untreated or treated with 1uM Thapsigargin (Tg) in triplicate. Both Total RNA and RNA isolated from ribosomal Immunoprecipitation (RIP) When unfolded proteins accumulate to irremediably high levels within the endoplasmic reticulum (ER), intracellular signaling pathways called the unfolded protein response (UPR) become hyperactivated to cause programmed cell death. We discovered that thioredoxin-interacting protein (TXNIP) is a critical node in this M-bM-^@M-^\Terminal UPRM-bM-^@M-^]. TXNIP becomes rapidly induced by hyperactivated IRE1a, an ER bifunctional kinase/endoribonuclease (RNase). IRE1a controls TXNIP mRNA stability by reducing levels of a TXNIP destabilizing micro-RNA, miR-17. In turn, elevated TXNIP protein activates the NLRP3 inflammasome, causing Caspase-1 cleavage and interleukin 1b (IL-1b) secretion. Txnip gene deletion reduces pancreatic b-cell death during ER stress, and suppresses diabetes caused by proinsulin misfolding in the Akita mouse. Finally, small molecule IRE1a RNase inhibitors suppress TXNIP production to block IL-1b secretion. In summary, the IRE1a-TXNIP pathway is used in the terminal UPR to promote sterile inflammation and programmed cell death, and may be targeted to develop new treatments for degenerative diseases driven by ER stress. There are 12 samples total all in INS-1 EGFP L10a cells- 3 untreated total RNA (reference sample), 3 treated with 1uM Tg 30 min total RNA, 3 untreated RIP RNA (reference sample), 3 treated with 1uM for 30 min RIP RNA

Dataset Information

Expression data from primary hepatocytes knocking down or overexpressing IRE1a

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets