MIST1 Links Secretion and Stress as both Target and Regulator of the Unfolded Protein Response

ABSTRACT Transcriptional networks that govern secretory cell specialization, including instructing cells to develop a unique cytoarchitecture, amass extensive protein synthesis machinery, and be embodied to respond to endoplasmic reticulum (ER) stress, remain largely uncharacterized. In this study, we discovered that the secretory cell transcription factor MIST1 (Bhlha15), previously shown to be essential for cytoskeletal organization and secretory activity, also functions as a potent ER stress-inducible transcriptional regulator. Genome-wide DNA binding studies, coupled with genetic mouse models, revealed MIST1 gene targets that function along the entire breadth of the protein synthesis, processing, transport, and exocytosis networks. Additionally, key MIST1 targets are essential for alleviating ER stress in these highly specialized cells. Indeed, MIST1 functions as a coregulator of the unfolded protein response (UPR) master transcription factor XBP1 for a portion of target genes that contain adjacent MIST1 and XBP1 binding sites. Interestingly, Mist1 gene expression is induced during ER stress by XBP1, but as ER stress subsides, MIST1 serves as a feedback inhibitor, directly binding the Xbp1 promoter and repressing Xbp1 transcript production. Together, our findings provide a new paradigm for XBP1-dependent UPR regulation and position MIST1 as a potential biotherapeutic for numerous human diseases.

[1]  M. Jiang,et al.  MIST1 and PTF1 Collaborate in Feed-Forward Regulatory Loops That Maintain the Pancreatic Acinar Phenotype in Adult Mice , 2016, Molecular and Cellular Biology.

[2]  R. Steele,et al.  Silencing Mist1 Gene Expression Is Essential for Recovery from Acute Pancreatitis , 2015, PloS one.

[3]  H. Nakauchi,et al.  The basic helix-loop-helix transcription factor, Mist1, induces maturation of mouse fetal hepatoblasts , 2015, Scientific Reports.

[4]  D. Langosch,et al.  Signal peptide peptidase functions in ERAD to cleave the unfolded protein response regulator XBP1u , 2014, The EMBO journal.

[5]  A. Saluja,et al.  Endoplasmic Reticulum Stress Is Chronically Activated in Chronic Pancreatitis* , 2014, The Journal of Biological Chemistry.

[6]  Jing Wang,et al.  WEB-based GEne SeT AnaLysis Toolkit (WebGestalt): update 2013 , 2013, Nucleic Acids Res..

[7]  Botond Penke,et al.  Proteome-wide study of endoplasmic reticulum stress induced by thapsigargin in N2a neuroblastoma cells , 2013, Neurochemistry International.

[8]  Wei-Guo Zhu,et al.  XBP-1u suppresses autophagy by promoting the degradation of FoxO1 in cancer cells , 2013, Cell Research.

[9]  H. Chung,et al.  Annals of the New York Academy of Sciences Unfolded Protein Response to Autophagy as a Promising Druggable Target for Anticancer Therapy , 2022 .

[10]  Yunlong Liu,et al.  Induced Mist1 expression promotes remodeling of mouse pancreatic acinar cells. , 2012, Gastroenterology.

[11]  R. Kaufman,et al.  The impact of the unfolded protein response on human disease , 2012, The Journal of cell biology.

[12]  C. Hetz,et al.  Targeting the UPR transcription factor XBP1 protects against Huntington's disease through the regulation of FoxO1 and autophagy. , 2012, Human molecular genetics.

[13]  N. Naidoo,et al.  The endoplasmic reticulum stress response in aging and age-related diseases , 2012, Front. Physio..

[14]  D. Direnzo Identifying Mist1 regulated genes in pancreatic acinar cell homeostasis and carcinogenesis , 2012 .

[15]  P. Taghert,et al.  Scaling factors: transcription factors regulating subcellular domains. , 2012, BioEssays : news and reviews in molecular, cellular and developmental biology.

[16]  Kenichi Yoshida,et al.  Gene regulatory network of unfolded protein response genes in endoplasmic reticulum stress , 2012, Cell stress & chaperones (Print).

[17]  R. Mehmood,et al.  The Absence of MIST1 Leads to Increased Ethanol Sensitivity and Decreased Activity of the Unfolded Protein Response in Mouse Pancreatic Acinar Cells , 2011, PloS one.

[18]  J. Varner,et al.  A review of the mammalian unfolded protein response , 2011, Biotechnology and bioengineering.

[19]  M. Soleimani,et al.  Slc26a11, a chloride transporter, localizes with the vacuolar H(+)-ATPase of A-intercalated cells of the kidney. , 2011, Kidney international.

[20]  L. Glimcher,et al.  Extensive pancreas regeneration following acinar-specific disruption of Xbp1 in mice. , 2011, Gastroenterology.

[21]  Laurie H Glimcher,et al.  The unfolded protein response: integrating stress signals through the stress sensor IRE1α. , 2011, Physiological reviews.

[22]  J. Debnath,et al.  PERK Integrates Autophagy and Oxidative Stress Responses To Promote Survival during Extracellular Matrix Detachment , 2011, Molecular and Cellular Biology.

[23]  D. Ron,et al.  Integrating the mechanisms of apoptosis induced by endoplasmic reticulum stress , 2011, Nature Cell Biology.

[24]  J. Klco,et al.  Transcription factor MIST1 in terminal differentiation of mouse and human plasma cells. , 2011, Physiological genomics.

[25]  John A. Williams Isolation of rodent pancreatic acinar cells and acini by collagenase digestion , 2010 .

[26]  L. Glimcher,et al.  XBP1 controls maturation of gastric zymogenic cells by induction of MIST1 and expansion of the rough endoplasmic reticulum. , 2010, Gastroenterology.

[27]  S. F. Konieczny,et al.  MIST1 regulates the pancreatic acinar cell expression of Atp2c2, the gene encoding secretory pathway calcium ATPase 2. , 2010, Experimental cell research.

[28]  J. Shea,et al.  Phenotype and Genotype of Pancreatic Cancer Cell Lines , 2010, Pancreas.

[29]  O. Homann,et al.  MochiView: versatile software for genome browsing and DNA motif analysis , 2010, BMC Biology.

[30]  Jason C. Mills,et al.  RAB26 and RAB3D Are Direct Transcriptional Targets of MIST1 That Regulate Exocrine Granule Maturation , 2009, Molecular and Cellular Biology.

[31]  Robert H. Brown,et al.  XBP-1 deficiency in the nervous system protects against amyotrophic lateral sclerosis by increasing autophagy. , 2009, Genes & development.

[32]  Mikael Bodén,et al.  MEME Suite: tools for motif discovery and searching , 2009, Nucleic Acids Res..

[33]  P. Fagone,et al.  ATF6α induces XBP1-independent expansion of the endoplasmic reticulum , 2009, Journal of Cell Science.

[34]  R. Hruban,et al.  Loss of the acinar-restricted transcription factor Mist1 accelerates Kras-induced pancreatic intraepithelial neoplasia. , 2009, Gastroenterology.

[35]  A. Koong,et al.  X box-binding protein 1 regulates angiogenesis in human pancreatic adenocarcinomas. , 2009, Translational oncology.

[36]  S. F. Konieczny,et al.  Mist1 regulates pancreatic acinar cell proliferation through p21 CIP1/WAF1. , 2008, Gastroenterology.

[37]  H. Tilg,et al.  XBP1 Links ER Stress to Intestinal Inflammation and Confers Genetic Risk for Human Inflammatory Bowel Disease , 2008, Cell.

[38]  C. Logsdon,et al.  Endoplasmic reticulum stress and the pancreatic acinar cell , 2008, Expert review of gastroenterology & hepatology.

[39]  P. Walter,et al.  Endoplasmic reticulum stress in disease pathogenesis. , 2008, Annual review of pathology.

[40]  Brad T. Sherman,et al.  Systematic and integrative analysis of large gene lists using DAVID bioinformatics resources , 2008, Nature Protocols.

[41]  D. Altshuler,et al.  Testing of diabetes-associated WFS1 polymorphisms in the Diabetes Prevention Program , 2008, Diabetologia.

[42]  M. Schröder Endoplasmic reticulum stress responses , 2008, Cellular and Molecular Life Sciences.

[43]  Chao Zhang,et al.  IRE1 Signaling Affects Cell Fate During the Unfolded Protein Response , 2007, Science.

[44]  R. Kaufman,et al.  ATF6alpha optimizes long-term endoplasmic reticulum function to protect cells from chronic stress. , 2007, Developmental cell.

[45]  Nathan H. Lents,et al.  XBP1 controls diverse cell type- and condition-specific transcriptional regulatory networks. , 2007, Molecular cell.

[46]  E. Fazio,et al.  Mice lacking the transcription factor Mist1 exhibit an altered stress response and increased sensitivity to caerulein-induced pancreatitis. , 2007, American journal of physiology. Gastrointestinal and liver physiology.

[47]  J. W. Brewer,et al.  Coordinate Regulation of Phospholipid Biosynthesis and Secretory Pathway Gene Expression in XBP-1(S)-induced Endoplasmic Reticulum Biogenesis* , 2007, Journal of Biological Chemistry.

[48]  S. F. Konieczny,et al.  The bHLH domain of Mistl is sufficient to activate gene transcription. , 2006, Gene expression.

[49]  T. Arumugam,et al.  Early activation of endoplasmic reticulum stress is associated with arginine-induced acute pancreatitis. , 2006, American journal of physiology. Gastrointestinal and liver physiology.

[50]  Gerald C. Chu,et al.  XBP‐1 is required for biogenesis of cellular secretory machinery of exocrine glands , 2005, The EMBO journal.

[51]  D. McConkey,et al.  Bortezomib inhibits PKR-like endoplasmic reticulum (ER) kinase and induces apoptosis via ER stress in human pancreatic cancer cells. , 2005, Cancer research.

[52]  M. Pino,et al.  Bortezomib sensitizes pancreatic cancer cells to endoplasmic reticulum stress-mediated apoptosis. , 2005, Cancer research.

[53]  Kathryn L. Lipson,et al.  WFS1 Is a Novel Component of the Unfolded Protein Response and Maintains Homeostasis of the Endoplasmic Reticulum in Pancreatic β-Cells* , 2005, Journal of Biological Chemistry.

[54]  Bing Zhang,et al.  WebGestalt: an integrated system for exploring gene sets in various biological contexts , 2005, Nucleic Acids Res..

[55]  S. Muallem,et al.  Aberrant Localization of Intracellular Organelles, Ca2+ Signaling, and Exocytosis in Mist1 Null Mice* , 2005, Journal of Biological Chemistry.

[56]  R. Kaufman,et al.  Differential contributions of ATF6 and XBP1 to the activation of endoplasmic reticulum stress-responsive cis-acting elements ERSE, UPRE and ERSE-II. , 2004, Journal of biochemistry.

[57]  A. Koong,et al.  XBP1 is essential for survival under hypoxic conditions and is required for tumor growth. , 2004, Cancer research.

[58]  S. F. Konieczny,et al.  Inhibition of Mist1 Homodimer Formation Induces Pancreatic Acinar-to-Ductal Metaplasia , 2004, Molecular and Cellular Biology.

[59]  N. Rajakumar,et al.  Mist1 is necessary for the establishment of granule organization in serous exocrine cells of the gastrointestinal tract , 2004, Mechanisms of Development.

[60]  L. Glimcher,et al.  XBP-1 Regulates a Subset of Endoplasmic Reticulum Resident Chaperone Genes in the Unfolded Protein Response , 2003, Molecular and Cellular Biology.

[61]  D. Lidington,et al.  Exocrine specific expression of Connexin32 is dependent on the basic helix-loop-helix transcription factor Mist1 , 2003, Journal of Cell Science.

[62]  K. Mori,et al.  XBP1 mRNA Is Induced by ATF6 and Spliced by IRE1 in Response to ER Stress to Produce a Highly Active Transcription Factor , 2001, Cell.

[63]  R. Hammer,et al.  The Role of PTF1-P48 in Pancreatic Acinar Gene Expression* , 2001, The Journal of Biological Chemistry.

[64]  S. F. Konieczny,et al.  The bHLH transcription factor Mist1 is required to maintain exocrine pancreas cell organization and acinar cell identity , 2001, The Journal of cell biology.

[65]  Neal N. Iwakoshi,et al.  Plasma cell differentiation requires the transcription factor XBP-1 , 2001, Nature.

[66]  S. F. Konieczny,et al.  Mist1 expression is a common link among serous exocrine cells exhibiting regulated exocytosis , 2000, The Anatomical record.

[67]  Peter Walter,et al.  Functional and Genomic Analyses Reveal an Essential Coordination between the Unfolded Protein Response and ER-Associated Degradation , 2000, Cell.

[68]  H. Lodish,et al.  Overview of the Secretory Pathway , 2000 .

[69]  S. F. Konieczny,et al.  The basic helix–loop–helix transcription factor Mist1 functions as a transcriptional repressor of MyoD , 1998, The EMBO journal.

[70]  R. Hammer,et al.  Differential requirements for cell-specific elastase I enhancer domains in transfected cells and transgenic mice. , 1989, Genes & development.

[71]  C. Michnoff,et al.  The Cell-Specific Elastase I Enhancer Comprises Two Domains , 1988, Molecular and cellular biology.

[72]  R. Kelly,et al.  Constitutive and regulated secretion of proteins. , 1987, Annual review of cell biology.

[73]  R. Hammer,et al.  Elastase I promoter directs expression of human growth hormone and SV40 T antigen genes to pancreatic acinar cells in transgenic mice. , 1985, Cold Spring Harbor symposia on quantitative biology.