Regulation of cellular iron homeostasis is crucial as both iron excess and deficiency cause hematological and neurodegenerative diseases. Here we show that mice lacking iron-regulatory protein 2 (Irp2), a regulator of cellular iron homeostasis, develop diabetes. Irp2 post-transcriptionally regulates the iron-uptake protein transferrin receptor 1 (TfR1) and the iron-storage protein ferritin, and dysregulation of these proteins due to Irp2 loss causes functional iron deficiency in β cells. This impairs Fe-S cluster biosynthesis, reducing the function of Cdkal1, an Fe-S cluster enzyme that catalyzes methylthiolation of t6A37 in tRNALysUUU to ms2t6A37. As a consequence, lysine codons in proinsulin are misread and proinsulin processing is impaired, reducing insulin content and secretion. Iron normalizes ms2t6A37 and proinsulin lysine incorporation, restoring insulin content and secretion in Irp2-/- β cells. These studies reveal a previously unidentified link between insulin processing and cellular iron deficiency that may have relevance to type 2 diabetes in humans.

Agilent Technologies 1 Yishun Ave 7 Singapore Singapore 768923

Antimicrobial Resistance Interdisciplinary Research Group Singapore MIT Alliance for Research and Technology 1 CREATE Way Singapore Singapore 138602

Celgene Corporation 1616 Eastlake Ave East Seattle WA 98102 USA

Chair of Experimental Genetics School of Life Science Weihenstephan Technische Universität München Alte Akademie 8 85354 Freising Germany

Czech Centre for Phenogenomics Institute of Molecular Genetics of the Czech Academy of Sciences Prumyslova 595 252 50 Vestec Czech Republic

Department of Biological Engineering Massachusetts Institute of Technology Cambridge MA 02139 USA

Department of Chemistry Massachusetts Institute of Technology Cambridge MA 02139 USA

Department of Medicine Division of Hematology University of Utah Salt Lake City UT 84112 USA

Department of Microbiology National University of Singapore Singapore Singapore 119077

Department of Oncological Sciences University of Utah Salt Lake City UT 84112 USA

German Center for Diabetes Research Ingolstädter Landstraße 1 85764 Neuherberg Germany

German Mouse Clinic Institute of Experimental Genetics Helmholtz Zentrum München Ingolstädter Landstraße 1 85764 Neuherberg Germany

Institute of Molecular Animal Breeding and Biotechnology Gene Center Ludwig Maximilians Universität München Feodor Lynen Strasse 25 81377 Munich Germany

Landstuhl Regional Medical Center 66849 Landstuhl Germany

Medizinische Hochschule Brandenburg Theodor Fontane Institut für Sozialmedizin und Epidemiologie 14770 Brandenburg an der Havel Germany

Molecular Medicine Program University of Utah Salt Lake City UT 84112 USA

Thermo Fisher Scientific Waltham MA 02451 USA

Zobrazit více v PubMed

Rajpathak SN, et al. The role of iron in type 2 diabetes in humans. Biochim. Biophys. Acta. 2009;1790:671–681. doi: 10.1016/j.bbagen.2008.04.005. PubMed DOI

Simcox JA, McClain DA. Iron and diabetes risk. Cell Metab. 2013;17:329–341. doi: 10.1016/j.cmet.2013.02.007. PubMed DOI PMC

Backe MB, Moen IW, Ellervik C, Hansen JB, Mandrup-Poulsen T. Iron regulation of pancreatic beta-cell functions and oxidative stress. Annu. Rev. Nutr. 2016;36:241–273. doi: 10.1146/annurev-nutr-071715-050939. PubMed DOI

Hansen JB, et al. Divalent metal transporter 1 regulates iron-mediated ROS and pancreatic beta cell fate in response to cytokines. Cell Metab. 2012;16:449–461. doi: 10.1016/j.cmet.2012.09.001. PubMed DOI

Cooksey RC, et al. Oxidative stress, beta-cell apoptosis, and decreased insulin secretory capacity in mouse models of hemochromatosis. Endocrinology. 2004;145:5305–5312. doi: 10.1210/en.2004-0392. PubMed DOI

Ristow M, et al. Frataxin deficiency in pancreatic islets causes diabetes due to loss of beta cell mass. J. Clin. Invest. 2003;112:527–534. doi: 10.1172/JCI18107. PubMed DOI PMC

Braymer JJ, Lill R. Iron-sulfur cluster biogenesis and trafficking in mitochondria. J. Biol. Chem. 2017;292:12754–12763. doi: 10.1074/jbc.R117.787101. PubMed DOI PMC

Netz DJ, Mascarenhas J, Stehling O, Pierik AJ, Lill R. Maturation of cytosolic and nuclear iron-sulfur proteins. Trends Cell Biol. 2014;24:303–312. doi: 10.1016/j.tcb.2013.11.005. PubMed DOI

Rouault TA. Mammalian iron-sulphur proteins: novel insights into biogenesis and function. Nat. Rev. Mol. Cell Biol. 2015;16:45–55. doi: 10.1038/nrm3909. PubMed DOI

Rouault TA. The role of iron regulatory proteins in mammalian iron homeostasis and disease. Nat. Chem. Biol. 2006;2:406–414. doi: 10.1038/nchembio807. PubMed DOI

Hentze MW, Muckenthaler MU, Galy B, Camaschella C. Two to tango: regulation of Mammalian iron metabolism. Cell. 2010;142:24–38. doi: 10.1016/j.cell.2010.06.028. PubMed DOI

Anderson CP, Shen M, Eisenstein RS, Leibold EA. Mammalian iron metabolism and its control by iron regulatory proteins. Biochim. Biophys. Acta. 2012;1823:1468–1483. doi: 10.1016/j.bbamcr.2012.05.010. PubMed DOI PMC

Vashisht AA, et al. Control of iron homeostasis by an iron-regulated ubiquitin ligase. Science. 2009;326:718–721. doi: 10.1126/science.1176333. PubMed DOI PMC

Salahudeen AA, et al. An E3 ligase possessing an iron-responsive hemerythrin domain is a regulator of iron homeostasis. Science. 2009;326:722–726. doi: 10.1126/science.1176326. PubMed DOI PMC

Cooperman SS, et al. Microcytic anemia, erythropoietic protoporphyria, and neurodegeneration in mice with targeted deletion of iron-regulatory protein 2. Blood. 2005;106:1084–1091. doi: 10.1182/blood-2004-12-4703. PubMed DOI PMC

Galy B, et al. Altered body iron distribution and microcytosis in mice deficient in iron regulatory protein 2 (IRP2) Blood. 2005;106:2580–2589. doi: 10.1182/blood-2005-04-1365. PubMed DOI

Zumbrennen-Bullough KB, et al. Abnormal brain iron metabolism in Irp2 deficient mice is associated with mild neurological and behavioral impairments. PLoS One. 2014;9:e98072. doi: 10.1371/journal.pone.0098072. PubMed DOI PMC

Jeong SY, et al. Iron insufficiency compromises motor neurons and their mitochondrial function in Irp2-null mice. PLoS One. 2011;6:e25404. doi: 10.1371/journal.pone.0025404. PubMed DOI PMC

Arragain S, et al. Identification of eukaryotic and prokaryotic methylthiotransferase for biosynthesis of 2-methylthio-N6-threonylcarbamoyladenosine in tRNA. J. Biol. Chem. 2010;285:28425–28433. doi: 10.1074/jbc.M110.106831. PubMed DOI PMC

Wei FY, et al. Deficit of tRNA(Lys) modification by Cdkal1 causes the development of type 2 diabetes in mice. J. Clin. Invest. 2011;121:3598–3608. doi: 10.1172/JCI58056. PubMed DOI PMC

Steinthorsdottir V, et al. A variant in CDKAL1 influences insulin response and risk of type 2 diabetes. Nat. Genet. 2007;39:770–775. doi: 10.1038/ng2043. PubMed DOI

Diabetes Genetics Initiative of Broad Institute of, H. et al. Genome-wide association analysis identifies loci for type 2 diabetes and triglyceride levels. Science. 2007;316:1331–1336. doi: 10.1126/science.1142358. PubMed DOI

Scott LJ, et al. A genome-wide association study of type 2 diabetes in Finns detects multiple susceptibility variants. Science. 2007;316:1341–1345. doi: 10.1126/science.1142382. PubMed DOI PMC

Zeggini E, et al. Replication of genome-wide association signals in UK samples reveals risk loci for type 2 diabetes. Science. 2007;316:1336–1341. doi: 10.1126/science.1142364. PubMed DOI PMC

Galy B, et al. Iron regulatory proteins secure mitochondrial iron sufficiency and function. Cell Metab. 2010;12:194–201. doi: 10.1016/j.cmet.2010.06.007. PubMed DOI

Arunagiri A, et al. Misfolded proinsulin in the endoplasmic reticulum during development of beta cell failure in diabetes. Ann. N. Y Acad. Sci. 2018;1418:5–19. doi: 10.1111/nyas.13531. PubMed DOI PMC

Back SH, Kaufman RJ. Endoplasmic reticulum stress and type 2 diabetes. Annu. Rev. Biochem. 2012;81:767–793. doi: 10.1146/annurev-biochem-072909-095555. PubMed DOI PMC

Papa FR. Endoplasmic reticulum stress, pancreatic beta-cell degeneration, and diabetes. Cold Spring Harb. Perspect. Med. 2012;2:a007666. doi: 10.1101/cshperspect.a007666. PubMed DOI PMC

Brambillasca S, et al. CDK5 regulatory subunit-associated protein 1-like 1 (CDKAL1) is a tail- anchored protein in the endoplasmic reticulum (ER) of insulinoma cells. J. Biol. Chem. 2012;287:41808–41819. doi: 10.1074/jbc.M112.376558. PubMed DOI PMC

Lill R, Srinivasan V, Muhlenhoff U. The role of mitochondria in cytosolic-nuclear iron-sulfur protein biogenesis and in cellular iron regulation. Curr. Opin. Microbiol. 2014;22C:111–119. doi: 10.1016/j.mib.2014.09.015. PubMed DOI

Koshimizu H, Kim T, Cawley NX, Loh YP. Chromogranin A: a new proposal for trafficking, processing and induction of granule biogenesis. Regul. Pept. 2010;160:153–159. doi: 10.1016/j.regpep.2009.12.007. PubMed DOI PMC

Groenewoud MJ, et al. Variants of CDKAL1 and IGF2BP2 affect first-phase insulin secretion during hyperglycaemic clamps. Diabetologia. 2008;51:1659–1663. doi: 10.1007/s00125-008-1083-z. PubMed DOI

Stancakova A, et al. Single-nucleotide polymorphism rs7754840 of CDKAL1 is associated with impaired insulin secretion in nondiabetic offspring of type 2 diabetic subjects and in a large sample of men with normal glucose tolerance. J. Clin. Endocrinol. Metab. 2008;93:1924–1930. doi: 10.1210/jc.2007-2218. PubMed DOI

Kirchhoff K, et al. Polymorphisms in the TCF7L2, CDKAL1 and SLC30A8 genes are associated with impaired proinsulin conversion. Diabetologia. 2008;51:597–601. doi: 10.1007/s00125-008-0926-y. PubMed DOI

Pascoe L, et al. Common variants of the novel type 2 diabetes genes CDKAL1 and HHEX/IDE are associated with decreased pancreatic beta-cell function. Diabetes. 2007;56:3101–3104. doi: 10.2337/db07-0634. PubMed DOI

Oslowski CM, Urano F. The binary switch that controls the life and death decisions of ER stressed beta cells. Curr. Opin. Cell Biol. 2011;23:207–215. doi: 10.1016/j.ceb.2010.11.005. PubMed DOI PMC

Muoio DM, Newgard CB. Mechanisms of disease: molecular and metabolic mechanisms of insulin resistance and beta-cell failure in type 2 diabetes. Nat. Rev. Mol. Cell Biol. 2008;9:193–205. doi: 10.1038/nrm2327. PubMed DOI

Ohara-Imaizumi M, et al. Deletion of CDKAL1 affects mitochondrial ATP generation and first-phase insulin exocytosis. PLoS One. 2010;5:e15553. doi: 10.1371/journal.pone.0015553. PubMed DOI PMC

Gabrielsen JS, et al. Adipocyte iron regulates adiponectin and insulin sensitivity. J. Clin. Invest. 2012;122:3529–3540. doi: 10.1172/JCI44421. PubMed DOI PMC

Gao Y, et al. Adipocyte iron regulates leptin and food intake. J. Clin. Invest. 2015;125:3681–3691. doi: 10.1172/JCI81860. PubMed DOI PMC

Hussain MA, Akalestou E, Song WJ. Inter-organ communication and regulation of beta cell function. Diabetologia. 2016;59:659–667. doi: 10.1007/s00125-015-3862-7. PubMed DOI PMC

Cantley J. The control of insulin secretion by adipokines: current evidence for adipocyte-beta cell endocrine signalling in metabolic homeostasis. Mamm. Genome. 2014;25:442–454. doi: 10.1007/s00335-014-9538-7. PubMed DOI

Tao C, Sifuentes A, Holland WL. Regulation of glucose and lipid homeostasis by adiponectin: effects on hepatocytes, pancreatic beta cells and adipocytes. Best. Pract. Res. Clin. Endocrinol. Metab. 2014;28:43–58. doi: 10.1016/j.beem.2013.11.003. PubMed DOI PMC

Take K, et al. CDK5 regulatory subunit-associated protein 1-like 1 negatively regulates adipocyte differentiation through activation of Wnt signaling pathway. Sci. Rep. 2017;7:7326. doi: 10.1038/s41598-017-06469-5. PubMed DOI PMC

Palmer CJ, et al. Cdkal1, a type 2 diabetes susceptibility gene, regulates mitochondrial function in adipose tissue. Mol. Metab. 2017;6:1212–1225. doi: 10.1016/j.molmet.2017.07.013. PubMed DOI PMC

Takesue Y, et al. Regulation of growth hormone biosynthesis by Cdk5 regulatory subunit associated protein 1-like 1 (CDKAL1) in pituitary adenomas. Endocr. J. 2019;66:807–816. doi: 10.1507/endocrj.EJ18-0536. PubMed DOI

Zhou Y, et al. Iron regulatory protein 2 deficiency may correlate with insulin resistance. Biochem. Biophys. Res. Commun. 2019;510:191–197. doi: 10.1016/j.bbrc.2019.01.022. PubMed DOI

Larrick JW, Hyman ES. Acquired iron-deficiency anemia caused by an antibody against the transferrin receptor. N. Engl. J. Med. 1984;311:214–218. doi: 10.1056/NEJM198407263110402. PubMed DOI

Hyman ES. Acquired iron-deficiency anaemia due to impaired iron transport. Lancet. 1983;1:91–95. doi: 10.1016/S0140-6736(83)91741-5. PubMed DOI

Rhodes CJ, et al. Iron deficiency and raised hepcidin in idiopathic pulmonary arterial hypertension: clinical prevalence, outcomes, and mechanistic insights. J. Am. Coll. Cardiol. 2011;58:300–309. doi: 10.1016/j.jacc.2011.02.057. PubMed DOI

Ruiter G, et al. Iron deficiency is common in idiopathic pulmonary arterial hypertension. Eur. Respir. J. 2011;37:1386–1391. doi: 10.1183/09031936.00100510. PubMed DOI

van Empel VP, Lee J, Williams TJ, Kaye DM. Iron deficiency in patients with idiopathic pulmonary arterial hypertension. Heart Lung Circ. 2014;23:287–292. doi: 10.1016/j.hlc.2013.08.007. PubMed DOI

von Haehling S, Jankowska EA, van Veldhuisen DJ, Ponikowski P, Anker SD. Iron deficiency and cardiovascular disease. Nat. Rev. Cardiol. 2015;12:659–669. doi: 10.1038/nrcardio.2015.109. PubMed DOI

Visanji NP, et al. Iron deficiency in parkinsonism: region-specific iron dysregulation in Parkinson’s disease and multiple system atrophy. J. Parkinsons Dis. 2013;3:523–537. doi: 10.3233/JPD-130197. PubMed DOI

Cotroneo E, et al. Iron homeostasis and pulmonary hypertension: iron deficiency leads to pulmonary vascular remodeling in the rat. Circ. Res. 2015;116:1680–1690. doi: 10.1161/CIRCRESAHA.116.305265. PubMed DOI

Matak P, et al. Disrupted iron homeostasis causes dopaminergic neurodegeneration in mice. Proc. Natl Acad. Sci. USA. 2016;113:3428–3435. doi: 10.1073/pnas.1519473113. PubMed DOI PMC

Cooper MS, Stark Z, Lunke S, Zhao T, Amor DJ. IREB2-associated neurodegeneration. Brain. 2019;142:e40. doi: 10.1093/brain/awz183. PubMed DOI

Costain G, et al. Absence of iron-responsive element-binding protein 2 causes a novel neurodegenerative syndrome. Brain. 2019;142:1195–1202. doi: 10.1093/brain/awz072. PubMed DOI PMC

Galy B, Ferring-Appel D, Kaden S, Grone HJ, Hentze MW. Iron regulatory proteins are essential for intestinal function and control key iron absorption molecules in the duodenum. Cell Metab. 2008;7:79–85. doi: 10.1016/j.cmet.2007.10.006. PubMed DOI

Neschen S, et al. Prevention of hepatic steatosis and hepatic insulin resistance in mitochondrial acyl- CoA:glycerol-sn-3-phosphate acyltransferase 1 knockout mice. Cell Metab. 2005;2:55–65. doi: 10.1016/j.cmet.2005.06.006. PubMed DOI

Neschen S, et al. n-3 Fatty acids preserve insulin sensitivity in vivo in a peroxisome proliferator- activated receptor-alpha-dependent manner. Diabetes. 2007;56:1034–1041. doi: 10.2337/db06-1206. PubMed DOI

Hohmeier HE, et al. Isolation of INS-1-derived cell lines with robust ATP-sensitive K+ channel- dependent and -independent glucose-stimulated insulin secretion. Diabetes. 2000;49:424–430. doi: 10.2337/diabetes.49.3.424. PubMed DOI

Zimmer M, et al. Small-molecule inhibitors of HIF-2a translation link its 5’UTR iron-responsive element to oxygen sensing. Mol. Cell. 2008;32:838–848. doi: 10.1016/j.molcel.2008.12.004. PubMed DOI PMC

Ran FA, et al. Genome engineering using the CRISPR-Cas9 system. Nat. Protoc. 2013;8:2281–2308. doi: 10.1038/nprot.2013.143. PubMed DOI PMC

Guo B, Yu Y, Leibold EA. Iron regulates cytoplasmic levels of a novel iron-responsive element- binding protein without aconitase activity. J. Biol. Chem. 1994;269:24252–24260. PubMed

Leibold EA, Munro HN. Cytoplasmic protein binds in vitro to a highly conserved sequence in the 5’ untranslated region of ferritin heavy- and light-subunit mRNAs. Proc. Natl Acad. Sci. USA. 1988;85:2171–2175. doi: 10.1073/pnas.85.7.2171. PubMed DOI PMC

Beaumont C, Torti SV, Torti FM, Massover WH. Novel properties of L-type polypeptide subunits in mouse ferritin molecules. J. Biol. Chem. 1996;271:7923–7926. doi: 10.1074/jbc.271.14.7923. PubMed DOI

Vendeix FA, et al. Human tRNA(Lys3)(UUU) is pre-structured by natural modifications for cognate and wobble codon binding through keto-enol tautomerism. J. Mol. Biol. 2012;416:467–485. doi: 10.1016/j.jmb.2011.12.048. PubMed DOI PMC