Abstract
It is known that β cell proliferation expands the β cell mass during development and under certain hyperglycemic conditions in the adult, a process that may be used for β cell regeneration in diabetes. Here, through a new high-throughput screen using a luminescence ubiquitination-based cell cycle indicator (LUCCI) in zebrafish, we identify HG-9-91-01 as a driver of proliferation and confirm this effect in mouse and human β cells. HG-9-91-01 is an inhibitor of salt-inducible kinases (SIKs), and overexpression of Sik1 specifically in β cells blocks the effect of HG-9-91-01 on β cell proliferation. Single-cell transcriptomic analyses of mouse β cells demonstrate that HG-9-91-01 induces a wave of activating transcription factor (ATF)6-dependent unfolded protein response (UPR) before cell cycle entry. Importantly, the UPR wave is not associated with an increase in insulin expression. Additional mechanistic studies indicate that HG-9-91-01 induces multiple signalling effectors downstream of SIK inhibition, including CRTC1, CRTC2, ATF6, IRE1 and mTOR, which integrate to collectively drive β cell proliferation.
This is a preview of subscription content, access via your institution
Access options
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 digital issues and online access to articles
$119.00 per year
only $9.92 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
Data availability
Raw and processed Smart-seq2 data are accessible at the Gene Expression Omnibus under accession GSE163972. UMAP plots for β cells treated with DMSO, harmine, HG or harmine and HG and gene-expression levels can be found at http://rshiny.nbis.se/shiny-server-apps/o_andersson/. Source data are provided with this paper.
References
Chen, C., Cohrs, C. M., Stertmann, J., Bozsak, R. & Speier, S. Human β cell mass and function in diabetes: recent advances in knowledge and technologies to understand disease pathogenesis. Mol. Metab. 6, 943–957 (2017).
Zhou, Q. & Melton, D. A. Pancreas regeneration. Nature 557, 351–358 (2018).
Wang, P. et al. Combined inhibition of DYRK1A, SMAD, and trithorax pathways synergizes to induce robust replication in adult human β cells. Cell Metab. 29, 638–652 (2019).
Wang, P. et al. A high-throughput chemical screen reveals that harmine-mediated inhibition of DYRK1A increases human pancreatic β cell replication. Nat. Med. 21, 383–388 (2015).
El Ouaamari, A. et al. SerpinB1 promotes pancreatic β cell proliferation. Cell Metab. 23, 194–205 (2016).
Ackeifi, C. et al. GLP-1 receptor agonists synergize with DYRK1A inhibitors to potentiate functional human β cell regeneration. Sci. Transl. Med. 12, eaaw9996 (2020).
Benthuysen, J. R., Carrano, A. C. & Sander, M. Advances in β cell replacement and regeneration strategies for treating diabetes. J. Clin. Invest. 126, 3651–3660 (2016).
Dor, Y., Brown, J., Martinez, O. I. & Melton, D. A. Adult pancreatic β-cells are formed by self-duplication rather than stem-cell differentiation. Nature 429, 41–46 (2004).
Meier, J. J. et al. β-cell replication is the primary mechanism subserving the postnatal expansion of β-cell mass in humans. Diabetes 57, 1584–1594 (2008).
Stolovich-Rain, M., Hija, A., Grimsby, J., Glaser, B. & Dor, Y. Pancreatic β cells in very old mice retain capacity for compensatory proliferation. J. Biol. Chem. 287, 27407–27414 (2012).
Teta, M., Long, S. Y., Wartschow, L. M., Rankin, M. M. & Kushner, J. A. Very slow turnover of β-cells in aged adult mice. Diabetes 54, 2557–2567 (2005).
Wang, P. et al. Diabetes mellitus—advances and challenges in human β-cell proliferation. Nat. Rev. Endocrinol. 11, 201–212 (2015).
Zeng, C. et al. Pseudotemporal ordering of single cells reveals metabolic control of postnatal β cell proliferation. Cell Metab. 25, 1160–1175 (2017).
Pisharath, H., Rhee, J. M., Swanson, M. A., Leach, S. D. & Parsons, M. J. Targeted ablation of β cells in the embryonic zebrafish pancreas using E. coli nitroreductase. Mech. Dev. 124, 218–229 (2007).
Curado, S. et al. Conditional targeted cell ablation in zebrafish: a new tool for regeneration studies. Dev. Dyn. 236, 1025–1035 (2007).
Bernal-Mizrachi, E. et al. Human β-cell proliferation and intracellular signaling part 2: still driving in the dark without a road map. Diabetes 63, 819–831 (2014).
Stewart, A. F. et al. Human β-cell proliferation and intracellular signaling: part 3. Diabetes 64, 1872–1885 (2015).
Shen, W. et al. Inhibition of DYRK1A and GSK3B induces human β-cell proliferation. Nat. Commun. 6, 8372 (2015).
Bader, E. et al. Identification of proliferative and mature β-cells in the islets of Langerhans. Nature 535, 430–434 (2016).
Klochendler, A. et al. The genetic program of pancreatic β-cell replication in vivo. Diabetes 65, 2081–2093 (2016).
Scharfmann, R. et al. Development of a conditionally immortalized human pancreatic β cell line. J. Clin. Invest. 124, 2087–2098 (2014).
Szabat, M. et al. Reduced insulin production relieves endoplasmic reticulum stress and induces β cell proliferation. Cell Metab. 23, 179–193 (2016).
Puri, S. et al. Replication confers β cell immaturity. Nat. Commun. 9, 485 (2018).
Hetz, C. The unfolded protein response: controlling cell fate decisions under ER stress and beyond. Nat. Rev. Mol. Cell Biol. 13, 89–102 (2012).
Papa, F. R. Endoplasmic reticulum stress, pancreatic β-cell degeneration, and diabetes. Cold Spring Harb. Perspect. Med. 2, a007666 (2012).
Wang, M. & Kaufman, R. J. Protein misfolding in the endoplasmic reticulum as a conduit to human disease. Nature 529, 326–335 (2016).
Sharma, R. B., Snyder, J. T. & Alonso, L. C. Atf6α impacts cell number by influencing survival, death and proliferation. Mol. Metab. 27S, S69–S80 (2019).
Shrestha, N., Reinert, R. B. & Qi, L. Endoplasmic reticulum protein quality control in β cells. Semin. Cell Dev. Biol. 103, 59–67 (2020).
Sharma, R. B. et al. Insulin demand regulates β cell number via the unfolded protein response. J. Clin. Invest. 125, 3831–3846 (2015).
Sakaue-Sawano, A. et al. Visualizing spatiotemporal dynamics of multicellular cell-cycle progression. Cell 132, 487–498 (2008).
Ninov, N. et al. Metabolic regulation of cellular plasticity in the pancreas. Curr. Biol. 23, 1242–1250 (2013).
Tsuji, N. et al. Whole organism high content screening identifies stimulators of pancreatic β-cell proliferation. PLoS ONE 9, e104112 (2014).
Andersson, O. et al. Adenosine signaling promotes regeneration of pancreatic β cells in vivo. Cell Metab. 15, 885–894 (2012).
Kushner, J. A. The role of aging upon β cell turnover. J. Clin. Invest. 123, 990–995 (2013).
Sakamaki, J. et al. Role of the SIK2–p35–PJA2 complex in pancreatic β-cell functional compensation. Nat. Cell Biol. 16, 234–244 (2014).
Clark, K. et al. Phosphorylation of CRTC3 by the salt-inducible kinases controls the interconversion of classically activated and regulatory macrophages. Proc. Natl Acad. Sci. USA 109, 16986–16991 (2012).
Picelli, S. et al. Full-length RNA-seq from single cells using Smart-seq2. Nat. Protoc. 9, 171–181 (2014).
Scialdone, A. et al. Computational assignment of cell-cycle stage from single-cell transcriptome data. Methods 85, 54–61 (2015).
Langfelder, P. & Horvath, S. WGCNA: an R package for weighted correlation network analysis. BMC Bioinformatics 9, 559 (2008).
Luo, Y. et al. Single-cell transcriptome analyses reveal signals to activate dormant neural stem cells. Cell 161, 1175–1186 (2015).
Luecken, M. D. & Theis, F. J. Current best practices in single-cell RNA-seq analysis: a tutorial. Mol. Syst. Biol. 15, e8746 (2019).
Saelens, W., Cannoodt, R., Todorov, H. & Saeys, Y. A comparison of single-cell trajectory inference methods. Nat. Biotechnol. 37, 547–554 (2019).
Wolf, F. A. et al. PAGA: graph abstraction reconciles clustering with trajectory inference through a topology preserving map of single cells. Genome Biol. 20, 59 (2019).
La Manno, G. et al. RNA velocity of single cells. Nature 560, 494–498 (2018).
Bergen, V., Lange, M., Peidli, S., Wolf, F. A. & Theis, F. J. Generalizing RNA velocity to transient cell states through dynamical modeling. Nat Biotechnol. 38, 1408–1414 (2020).
Engin, F. et al. Restoration of the unfolded protein response in pancreatic β cells protects mice against type 1 diabetes. Sci. Transl. Med. 5, 211ra156 (2013).
Surani, M. A. Glycoprotein synthesis and inhibition of glycosylation by tunicamycin in preimplantation mouse embryos: compaction and trophoblast adhesion. Cell 18, 217–227 (1979).
Altarejos, J. Y. & Montminy, M. CREB and the CRTC co-activators: sensors for hormonal and metabolic signals. Nat. Rev. Mol. Cell Biol. 12, 141–151 (2011).
Berdeaux, R. & Hutchins, C. Anabolic and pro-metabolic functions of CREB–CRTC in skeletal muscle: advantages and obstacles for type 2 diabetes and cancer cachexia. Front. Endocrinol. 10, 535 (2019).
Eberhard, C. E., Fu, A., Reeks, C. & Screaton, R. A. CRTC2 is required for β-cell function and proliferation. Endocrinology 154, 2308–2317 (2013).
Wang, Y., Vera, L., Fischer, W. H. & Montminy, M. The CREB coactivator CRTC2 links hepatic ER stress and fasting gluconeogenesis. Nature 460, 534–537 (2009).
Allen, D. & Seo, J. ER stress activates the TOR pathway through Atf6. J. Mol. Signal 13, 1 (2018).
Blackwood, E. A. et al. ATF6 regulates cardiac hypertrophy by transcriptional induction of the mTORC1 activator, Rheb. Circ. Res. 124, 79–93 (2019).
Wullschleger, S., Loewith, R. & Hall, M. N. TOR signaling in growth and metabolism. Cell 124, 471–484 (2006).
Blackwood, E. A. et al. Pharmacologic ATF6 activation confers global protection in widespread disease models by reprograming cellular proteostasis. Nat. Commun. 10, 187 (2019).
Plate, L. et al. Small molecule proteostasis regulators that reprogram the ER to reduce extracellular protein aggregation. eLife 5, e15550 (2016).
Hussain, M. A. et al. Increased pancreatic β-cell proliferation mediated by CREB binding protein gene activation. Mol. Cell. Biol. 26, 7747–7759 (2006).
Xu, T. et al. The IRE1α–XBP1 pathway regulates metabolic stress-induced compensatory proliferation of pancreatic β-cells. Cell Res. 24, 1137–1140 (2014).
Ardestani, A., Lupse, B., Kido, Y., Leibowitz, G. & Maedler, K. mTORC1 signaling: a double-edged sword in diabetic β cells. Cell Metab. 27, 314–331 (2018).
Blandino-Rosano, M. et al. mTORC1 signaling and regulation of pancreatic β-cell mass. Cell Cycle 11, 1892–1902 (2012).
Yang, W., Sheng, F., Sun, B., Fischbach, S. & Xiao, X. The role of ORMDL3/ATF6 in compensated β cell proliferation during early diabetes. Aging 11, 2787–2796 (2019).
Sakamoto, K., Bultot, L. & Goransson, O. The salt-inducible kinases: emerging metabolic regulators. Trends Endocrinol. Metab. 29, 827–840 (2018).
Wein, M. N., Foretz, M., Fisher, D. E., Xavier, R. J. & Kronenberg, H. M. Salt-inducible kinases: physiology, regulation by cAMP, and therapeutic potential. Trends Endocrinol. Metab. 29, 723–735 (2018).
Kim, M. J. et al. Salt-inducible kinase 1 terminates cAMP signaling by an evolutionarily conserved negative-feedback loop in β-cells. Diabetes 64, 3189–3202 (2015).
Koo, S. H. et al. The CREB coactivator TORC2 is a key regulator of fasting glucose metabolism. Nature 437, 1109–1111 (2005).
Patel, K. et al. The LKB1–salt-inducible kinase pathway functions as a key gluconeogenic suppressor in the liver. Nat. Commun. 5, 4535 (2014).
Nixon, M. et al. Skeletal muscle salt inducible kinase 1 promotes insulin resistance in obesity. Mol. Metab. 5, 34–46 (2016).
Adachi, Y. et al. ATF6 is a transcription factor specializing in the regulation of quality control proteins in the endoplasmic reticulum. Cell Struct. Funct. 33, 75–89 (2008).
Sharma, R. B., Darko, C. & Alonso, L. C. Intersection of the ATF6 and XBP1 ER stress pathways in mouse islet cells. J. Biol. Chem. 295, 14164–14177 (2020).
Shoulders, M. D. et al. Stress-independent activation of XBP1s and/or ATF6 reveals three functionally diverse ER proteostasis environments. Cell Rep. 3, 1279–1292 (2013).
Yamamoto, K. et al. Transcriptional induction of mammalian ER quality control proteins is mediated by single or combined action of ATF6α and XBP1. Dev. Cell 13, 365–376 (2007).
Yamamoto, K., Yoshida, H., Kokame, K., Kaufman, R. J. & Mori, K. Differential contributions of ATF6 and XBP1 to the activation of endoplasmic reticulum stress-responsive cis-acting elements ERSE, UPRE and ERSE-II. J. Biochem. 136, 343–350 (2004).
Xin, Y. et al. Pseudotime ordering of single human β-cells reveals states of insulin production and unfolded protein response. Diabetes 67, 1783–1794 (2018).
De Vas, M. & Ferrer, J. Can insulin production suppress β cell growth? Cell Metab. 23, 4–5 (2016).
Balboa, D. et al. Insulin mutations impair β-cell development in a patient-derived iPSC model of neonatal diabetes. eLife 7, e38519 (2018).
Riahi, Y. et al. Inhibition of mTORC1 by ER stress impairs neonatal β-cell expansion and predisposes to diabetes in the Akita mouse. eLife 7, e38472 (2018).
Tatsuoka, H. et al. Single-cell transcriptome analysis dissects the replicating process of pancreatic β cells in partial pancreatectomy model. iScience 23, 101774 (2020).
Thermes, V. et al. I-SceI meganuclease mediates highly efficient transgenesis in fish. Mech. Dev. 118, 91–98 (2002).
Lyon, J. et al. Research-focused isolation of human islets from donors with and without diabetes at the Alberta Diabetes Institute IsletCore. Endocrinology 157, 560–569 (2016).
Sundberg, T. B. et al. Development of chemical probes for investigation of salt-inducible kinase function in vivo. ACS Chem. Biol. 11, 2105–2111 (2016).
Yu, Z., Huang, Z. & Lung, M. L. Subcellular fractionation of cultured human cell lines. Bio Protoc. 3, e754 (2013).
Ramskold, D., Wang, E. T., Burge, C. B. & Sandberg, R. An abundance of ubiquitously expressed genes revealed by tissue transcriptome sequence data. PLoS Comput. Biol. 5, e1000598 (2009).
Acknowledgements
We thank J. Avila for assistance with flow cytometry, F. Salomons for assistance with ImageXpress and C. Karampelias and K.-C. Liu for discussions. Human islets for research were provided by the Alberta Diabetes Institute IsletCore at the University of Alberta (www.bcell.org/adi-isletcore) and the Integrated Islet Distribution Program (https://iidp.coh.org). Single-cell transcriptome data were generated at the Eukaryotic Single-Cell Genomics facility at SciLifeLab in Stockholm, Sweden. Computations and data handling were enabled by resources provided by the Swedish National Infrastructure for Computing (SNIC) at the UPPMAX, partially funded by the Swedish Research Council through grant agreement no. 2018-05973. This work was supported by grants from the following organisations: the Swedish Research Council, the Novo Nordisk Foundation, the Swedish Diabetes Foundation, the Ragnar Söderberg’s Foundation and Strategic Research Programmes in Diabetes, Stem Cell Research & Regenerative Medicine at the Karolinska Institutet to O.A.; and NIH/NIDDK (R01DK114686, R01DK113300) and the George F. and Sybil H. Fuller Foundation to L.C.A.; A.J. and R.Å. were financially supported by the Knut and Alice Wallenberg Foundation as part of the National Bioinformatics Infrastructure Sweden at SciLifeLab.
Author information
Authors and Affiliations
Contributions
J.C., L.R. and D.T. performed and analysed results from the zebrafish experiments. L.R. performed the mechanistic biochemical and cell culture experiments. J.C., L.C. and N.S. performed in vivo mouse experiments. P.W. and A.F.S. performed the human islet experiments and analysed the data. J.C., A.J., R.Å. and P.C. analysed scRNA-seq data. R.B.S. and L.C.A performed the mouse experiments displayed in Fig. 7 and analysed the data. J.C. and O.A. designed, performed and analysed zebrafish and mouse experiments and wrote the manuscript with input from all authors. O.A. is the guarantor of this work and, as such, had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Peer review information Nature Metabolism thanks the anonymous reviewers for their contribution to the peer review of this work. Primary Handling Editors: Elena Bellafante; Isabella Samuelson.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Extended data
Extended Data Fig. 1 In vivo chemical screen identifies stimulators of β-cell proliferation in zebrafish (related to Fig. 1).
(a) Validation of the LUCCI assay using NECA as a positive control in the basal state and during β-cell regeneration. Data in the basal state: N = 28 (DMSO), N = 13 (NECA 50 µM), and N = 32 (NECA 100 µM) wells. Data during regeneration: N = 30 (DMSO), N = 33 (NECA 50 µM), and N = 34 (NECA 100 µM) wells. One-way ANOVA with Tukey’s multiple comparisons test, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001. Data are represented as the mean ± SEM. (b) Scatterplot of the efficacy of the hits identified during the basal state. PI3K: phosphoinositide 3-kinase. RTK: receptor tyrosine kinase. S/TK: serine/threonine kinase. (c) Dose-response activity of Lini and of HG. Tg(ins:NLuc-gmnn) or Tg(ins:NLuc-gmnn);Tg(ins:flag-NTR) larvae were treated with Lini or HG for 2 days (from 4 to 6 dpf), respectively. For Lini: N = 8 wells for X = −6.5; N = 11 wells for X = −6 and X = −5.3; N = 12 wells for X = −5; N = 15 for X = −5.7 and X = −4.7. For HG: N = 5 wells for X = −4.4, X = −4.7, X = −5 and X = −5.3. Data are represented as the mean ± SEM. A second order polynomial equation was used for modelling the bell-shaped curve. R2 = 0.13 for Lini and R2 = 0.32 for HG. (d) Effect of HG and Lini on the LUCCI signal under two conditions: in the basal state and during β-cell regeneration. Data in the basal state: N = 8 (DMSO), N = 8 (HG), and N = 6 (Lini) wells. Data during regeneration: N = 16 (DMSO), N = 10 (HG) and N = 5 (Lini) wells. One-way ANOVA with Tukey’s multiple comparisons test, ***P ≤ 0.001, ****P ≤ 0.0001. Data are represented as the mean ± SEM. (e) Number of β-cells in Tg(ins:H2B-GFP) larvae treated with DMSO or Lini from 4 to 6 dpf. Two-sided student’s t-test, ****P ≤ 0.0001. N = 23 (DMSO) and 9 (Lini) larvae. Data are represented as the mean ± SEM.
Extended Data Fig. 2 HG increases the proliferation of both mouse and human β-cells (related to Fig. 2).
(a) Effect of combined treatment with Harm and HG on β-cell proliferation in regenerating zebrafish. N = 5 wells per condition except for Harm 10 µM where N = 4. One-way ANOVA with Tukey’s multiple comparisons test, *P ≤ 0.05. Data are represented as the mean ± SEM. (b) Quantification of the percentage of proliferating α-, δ-, and β-cells after treatment with HG in regenerating zebrafish and mouse. Two-sided student’s t-test, *** P ≤ 0.001, ****P ≤ 0.0001. ****P ≤ 0.0001. Data are represented as the mean ± SEM. Data with the number of cells in zebrafish: N = 29 (gcga:GFP, DMSO), N = 27 (gcga:GFP, HG), N = 22 (sst2:RFP, DMSO), N = 29 (sst2:RFP, HG), N = 33 (ins:GFP, DMSO) and N = 34 (ins:GFP, HG) larvae. Data with the number of EdU+ cells in zebrafish: N = 47 (gcga:GFP, DMSO), N = 43 (gcga:GFP, HG), N = 36 (sst2:RFP, DMSO), N = 45 (sst2:RFP, HG), N = 46 (ins:GFP, DMSO) and N = 50 (ins:GFP, HG) larvae. Data with the percentage of proliferative cells from mouse: N = 11 (for sst and gcg, DMSO and HG), N = 38 (ins, DMSO), and N = 29 (ins, HG) wells. (c) Detection of apoptosis in mouse β-cells after 48 and 96 h of treatment. DNase I was used as positive control. N = 2 mice per treatment and time, except for the positive control DNAse I (N = 1). (d) Quantification of the percentage proliferative β-cells from 1.5-year-old mice after 96 h of culture of dissociated mouse islets. One-way ANOVA with Tukey’s multiple comparisons test, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001. For data with Ki-67 and EdU: N = 8 (DMSO), N = 7 (Lini) and N = 9 (Harm, HG, and Harm + HG) mice. Data are represented as the mean ± SEM. (e) Assessment of β-cell functionality after 4 days treatment with DMSO or HG in low or high glucose medium. N = 4 wells per condition. One-way ANOVA with Tukey’s multiple comparisons test, *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001. Data are represented as the mean ± SEM. (f) Quantification of the percentage proliferative β-cells in cultures of dissociated human islets after treatment with DMSO or Lini for 96 h. N = 4 donors.
Extended Data Fig. 3 Single-cell RNA-seq of β-cells reveals characteristic transcriptional signatures (related to Fig. 4).
(a) FACS of wild-type islet cells. An example is shown with HG-treated cells. The 7-AAD was added to deselect proapoptotic cells. Different gates based on the forward-scatter vs. side-scatter (P1), width of the forward-scatter (P2) and the side-scatter (P3) and Cy5neg (7-AADneg, P4) cells were applied before sorting the cells into 384-well plates. (b-j) Pre-processing: Quality Control (QC) and feature selection. (b) Experimental setup: Each plate (PU: plate unit) corresponds to one experiment. Similar conditions between experiments are outlined in different colors, showing partial experimental overlap from one plate to another. (c) QC covariates: Filtering criterion (upper panel) histogram for count gene/count depth (middle panel), histogram for gene detection (lower panel). Failed cells are shown in red, and the cutoff value is indicated in the upper panel. (d) Summary of QC statistics. The total number of cells below the cutoff value for each criterion is shown along the diagonal. (e) The number of cells per identity: the molecular marker for each cellular identity and the gene cutoff value for each marker are indicated. (f) The number of β-cells per condition (plate unit, treatment time, and compound treatment). (g) Principal component analysis underscoring the cell distribution according to 3 conditions: PU, treatment time, and compound treatment. Note the marked distribution heterogeneity according to PU and treatment time as compared to the compound treatment. (h) Explained variance for different QC covariates/batch information. The density plots show how much of the variance in expression of the genes can be explained by the various QC covariates/batch information. The vertical line indicates 1%, meaning that the genes to the left of that line have a small correlation with the covariate/batch information. The gene detection covariate explains a large amount of the variance, in contrast to PU. (i) Correlations of the most important features to principal components 1 and 2 (PC1 and PC2). (j) Feature selection: The 500 most highly variable genes are shown in blue.
Extended Data Fig. 4 The UPR is necessary for HG-induced β-cell proliferation (related to Fig. 7).
(a) mRNA levels of genes belonging to the ATF6, IRE1, or PERK pathways after treatment of mouse islet cells with DMSO or HG in low glucose medium. N = 3 independent experiments. Two-sided student’s t-test. **P = 0.001 for Sec24d, ***P ≤ 0.001 for Pdia4. (b) In vivo effect of HG (10 mg/kg) on UPR activation in wild-type mice. Left panel: Representative images of islets from control and HG-treated mice after 14 h of treatment. Scale bar: 20 µm. In blue: DAPI; in green: insulin; in red: BIP. The arrows show BIP+ β-cells. Right panel: Quantification of the percentage of mouse β-cells expressing BIP per islet. Data are represented as the mean ± SEM. Two-sided student’s t-test. **P = 0.0032. N = 123 islets from 6 HG-treated mice and 131 islets from 6 control-treated mice.
Extended Data Fig. 5 HG engages several downstream effectors leading to β-cell proliferation (related to Fig. 8).
(a) Time-course of the Tm effect on ATF6-N and BIP protein levels in MIN6 cells. Left panel: Representative immunoblot with GAPDH used as a loading control. Right panel: Quantification of ATF6-N and BIP relative protein expression over time. N = 3 independent experiments per time point. (b) Immunoprecipitation experiments to examine a potential direct interaction of ATF6 with SIK1. Upper panel: Experimental workflow. HEK cells were transfected with a Myc-Flag-SIK1 plasmid and treated with DMSO or HG for 6 h. After incubation of cell lysates with anti-Flag antibodies and immunoprecipitation, samples were immunoblotted using anti-ATF6 or anti-Flag antibodies. Lower-left panel: The negative control corresponds to non-transfected HEK cells (Neg). The input displays an ATF6 band that is not detected in the samples after immunoprecipitation with anti-Flag (SIK1). Lower-right panel: The input and IP show the presence of Flag-tagged SIK1 in the samples. One representative experiment out of 2 is shown. (c) Immunoprecipitation experiments to examine the phosphorylation of ATF6 at Ser/Thr residues. Upper panel: Experimental workflow. HEK cells were transfected with a Flag-ATF6 plasmid and treated with DMSO or HG for 6 h. After incubation of cell lysates with anti-Flag antibodies and immunoprecipitation, samples were immunoblotted using anti-phospho-Ser/Thr or anti-ATF6. Lower-left panel: The negative control corresponds to IP lysis buffer (Neg). The input shows phosphorylation marks (indicated by arrows, ph) in both DMSO or HG-treated cells, marks that are no longer detected in the samples after immunoprecipitation with anti-Flag (ATF6). Lower-right panel: The input and IP show the presence of an ATF6 band in the samples. One representative experiment out of 2 is shown.
Supplementary information
Supplementary Tables
Supplementary Tables 1–8
Source data
Source Data Fig. 3
Unprocessed gels.
Source Data Fig. 7
Unprocessed western blots and gels.
Source Data Fig. 8
Unprocessed western blots.
Source Data Extended Data Fig. 5
Unprocessed western blots.
Rights and permissions
About this article
Cite this article
Charbord, J., Ren, L., Sharma, R.B. et al. In vivo screen identifies a SIK inhibitor that induces β cell proliferation through a transient UPR. Nat Metab 3, 682–700 (2021). https://doi.org/10.1038/s42255-021-00391-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/s42255-021-00391-x
This article is cited by
-
Adjudin improves beta cell maturation, hepatic glucose uptake and glucose homeostasis
Diabetologia (2024)
-
Inhibition of mammalian mtDNA transcription acts paradoxically to reverse diet-induced hepatosteatosis and obesity
Nature Metabolism (2024)
-
Salt-inducible kinases inhibitor HG-9-91-01 targets RIPK3 kinase activity to alleviate necroptosis-mediated inflammatory injury
Cell Death & Disease (2022)
-
MNK2 deficiency potentiates β-cell regeneration via translational regulation
Nature Chemical Biology (2022)