المؤلفون: Beumer, Joep, Bauzá-Martinez, Julia, Veth, Tim S., Geurts, Veerle, Boot, Charelle, Gilliam-Vigh, Hannah, Poulsen, Steen S., Knop, Filip K., Wu, Wei, Clevers, Hans

المساهمون: Hubrecht Institute with UMC, CMM, Cancer

مصطلحات موضوعية: CRISPR-Cas9, enteroendocrine cells, intestinal organoids, peptidomics, prohormone processing, General

الوصف: Enteroendocrine cells (EECs) secrete hormones in response to ingested nutrients to control physiological processes such as appetite and insulin release. EEC hormones are synthesized as large proproteins that undergo proteolytic processing to generate bioactive peptides. Mutations in EEC-enriched proteases are associated with endocrinopathies. Due to the relative rarity of EECs and a paucity of in vitro models, intestinal prohormone processing remains challenging to assess. Here, human gut organoids in which EECs can efficiently be induced are subjected to CRISPR-Cas9–mediated modification of EEC-expressed endopeptidase and exopeptidase genes. We employ mass spectrometry–based analyses to monitor peptide processing and identify glucagon production in intestinal EECs, stimulated upon bone morphogenic protein (BMP) signaling. We map the substrates and products of major EECs endo- and exopeptidases. Our studies provide a comprehensive description of peptide hormones produced by human EECs and define the roles of specific proteases in their generation.

وصف الملف: application/pdf

العلاقة: https://dspace.library.uu.nl/handle/1874/447917Test

الإتاحة: https://dspace.library.uu.nl/handle/1874/447917Test

المؤلفون: Sofia Ferreira, Ana F. Raimundo, Inês Farrim, Regina Menezes

المصدر: Journal Biomedical and Biopharmaceutical Research (BBR), Vol 19, Iss 2, Pp 337-354 (2022)

مصطلحات موضوعية: amilina, polipéptido, amilóide dos ilhéus (iapp), kexina 2, processamento de pro-hormonas, saccharomyces cerevisiae, amylin, islet amyloid polypeptide (iapp), kexin 2, prohormone processing, Therapeutics. Pharmacology, RM1-950

الوصف: Pancreatic deposition of Islet Amyloid PolyPeptide (IAPP) is a histopathological hallmark of type 2 diabetes. Inadequate processing of immature IAPP by proprotein convertases (PCs) leads to the accumulation of unprocessed forms, which in turn favors increased aggregate formation in pancreatic β-cells. Kexin 2 (Kex2) of Saccharomyces cerevisiae is the prototype of eukaryotic PCs family, but to date no direct correlations between Kex2 activity and preproIAPP processing in yeast have been reported. In this study we aimed to address the possible role of Kex2 on IAPP maturation as a tool to investigate the contribution of impaired processing towards IAPP proteototoxicity. Genetically modified S. cerevisiae models lacking the KEX2 gene and carrying different chimeric fusions of human IAPP linked to GFP were used. The cytotoxic effects of Kex2 ablation were assessed by means of growth curve analysis and cell viability assays using flow cytometry. IAPP protein profile was evaluated by immunoblotting assays using an anti-IAPP antibody. Intracellular IAPP aggregates were monitored by confocal fluorescence microscopy. Data showed that kex2 mutants exhibit growth defects, potentiated by preproIAPP-GFP, proIAPP-GFP and mature IAPP-GFP expression with an increased cytotoxicity for proIAPP-GFP. Notwithstanding, Kex2 absence does not seem to affect IAPP protein pattern nor the frequency/distribution of intracellular IAPP aggregates in yeast. Our findings suggest that Kex2 is not essential for IAPP processing in yeast, at least under the conditions tested. Resumo A deposição pancreática do Polipéptido Amilóide dos Ilhéus (IAPP) é uma marca histopatológica da diabetes tipo 2. O processamento inadequado de IAPP imaturo pelas proproteínas convertases (PCs) despoleta a acumulação de formas não processadas que favorecem o aumento da formação de agregados nas células β. A Kexina 2 (Kex2) de Saccharomyces cerevisiae é o protótipo da família das PCs eucarióticas. Contudo, até ao momento, não existem evidências da ação da Kex2 no ...

العلاقة: https://www.alies.pt/BBR%20Editions/Vol-19-2-2022/bbr.19.2.301.pdfTest; https://doaj.org/toc/2182-2379Test; https://doaj.org/article/a9b85f4c8254466db275361cd8fd418fTest

الإتاحة: https://doi.org/10.19277/bbr.19.2.301Test
https://doaj.org/article/a9b85f4c8254466db275361cd8fd418fTest

المؤلفون: Park, Chung‐Mo, Bruenn, Jeremy A., Ganesa, Chandrashekar, Flurkey, William F., Bozarth, Robert F., Koltin, Yigal

المساهمون: Park, Chung‐Mo

مصطلحات موضوعية: DOUBLE-STRANDED-RNA, PROHORMONE-PROCESSING ENZYME, KILLER TOXIN, SACCHAROMYCES-CEREVISIAE, MAMMALIAN-CELLS, GENE ENCODES, ALPHA-FACTOR, YEAST, PROTEASE, VIRUS

الوصف: Killer toxins are polypeptides secreted by some fungal species that kill sensitive cells of the same or related species. In the best-characterized cases, they function by creating new pores in the cell membrane and disrupting ion fluxes. Immunity or resistance to the toxins is conferred by the preprotoxins (or products thereof) or by nuclear resistance genes. In several cases, the toxins are encoded by one or more genomic segments of resident double-stranded RNA viruses. The known toxins are composed of one to three polypeptides, usually present as multimers. We have further characterized the KP4 killer toxin from the maize smut fungus Ustilago maydis. This toxin is also encoded by a single viral double-stranded RNA but differs from other known killer toxins in several respects: it has no N-linked glycosylation either in the precursor or in the mature polypeptide, it is the first killer toxin demonstrated to be a single polypeptide, and it is not processed by any of the known secretory proteinases (other than the signal peptidase). It is efficiently expressed in a heterologous fungal system. ; N ; 1

العلاقة: Molecular Microbiology, Vol.11 No.1, pp.155-164; https://hdl.handle.net/10371/190010Test; A1994MQ20600016; 2-s2.0-0028306740; 147992

الإتاحة: https://doi.org/10.1111/j.1365-2958.1994.tb00297.xTest
https://hdl.handle.net/10371/190010Test

المؤلفون: Sam G. Galvin (11313930), Richard G. Kay (2327857), Rachel Foreman (11313933), Pierre Larraufie (6067598), Claire L. Meek (7242761), Emma Biggs (11313936), Peter Ravn (494111), Lutz Jermutus (608646), Frank Reimann (707211), Fiona M. Gribble (7242782)

مصطلحات موضوعية: Biochemistry, Cell Biology, Molecular Biology, Physiology, Biotechnology, Immunology, Developmental Biology, Virology, Chemical Sciences not elsewhere classified, mouse pancreatic islets, GIP, Type 2 Diabetes, islet insulin production, Glucose-dependent insulinotropic pe., Mouse Islet Peptidome, GLP, mouse islet incubations, LC-MS, prohormone processing defects, mouse islets

الوصف: To characterize the impact of metabolic disease on the peptidome of human and mouse pancreatic islets, LC-MS was used to analyze extracts of human and mouse islets, purified mouse alpha, beta, and delta cells, supernatants from mouse islet incubations, and plasma from patients with type 2 diabetes. Islets were obtained from healthy and type 2 diabetic human donors, and mice on chow or high fat diet. All major islet hormones were detected in lysed islets as well as numerous peptides from vesicular proteins including granins and processing enzymes. Glucose-dependent insulinotropic peptide (GIP) was not detectable. High fat diet modestly increased islet content of proinsulin-derived peptides in mice. Human diabetic islets contained increased content of proglucagon-derived peptides at the expense of insulin, but no evident prohormone processing defects. Diabetic plasma, however, contained increased ratios of proinsulin and des-31,32-proinsulin to insulin. Active GLP-1 was detectable in human and mouse islets but 100–1000-fold less abundant than glucagon. LC-MS offers advantages over antibody-based approaches for identifying exact peptide sequences, and revealed a shift toward islet insulin production in high fat fed mice, and toward proglucagon production in type 2 diabetes, with no evidence of systematic defective prohormone processing.

العلاقة: https://figshare.com/articles/journal_contribution/The_Human_and_Mouse_Islet_Peptidome_Effects_of_Obesity_and_Type_2_Diabetes_and_Assessment_of_Intraislet_Production_of_Glucagon-like_Peptide_1/16411344Test

الإتاحة: https://doi.org/10.1021/acs.jproteome.1c00463.s001Test

المؤلفون: Greenwood, Mingkwan, Paterson, Alex, Rahman, Parveen Akhter, Gillard, Benjamin Thomas, Langley, Sydney, Iwasaki, Yasumasa, Murphy, David, Greenwood, Michael Paul

المصدر: Greenwood , M , Paterson , A , Rahman , P A , Gillard , B T , Langley , S , Iwasaki , Y , Murphy , D & Greenwood , M P 2020 , ' Transcription factor Creb3l1 regulates the synthesis of prohormone convertase enzyme PC1/3 in endocrine cells ' , Journal of Neuroendocrinology , vol. 32 , no. 4 , E12851 . https://doi.org/10.1111/jne.12851Test

مصطلحات موضوعية: dehydration, pituitary, POMC, prohormone processing, supraoptic nucleus, transcription

الوصف: Transcription factor cAMP responsive element‐binding protein 3 like 1 (Creb3l1) is a non‐classical endoplasmic reticulum stress molecule that is emerging as an important component for cellular homeostasis, particularly within cell types with high peptide secretory capabilities. We have previously shown that Creb3l1 serves an important role in body fluid homeostasis through its transcriptional control of the gene coding for antidiuretic hormone arginine vasopressin in the neuropeptide‐rich magnocellular neurones of the supraoptic nucleus. In response to osmotic stimuli such as dehydration, vasopressin magnocellular neurones undergo remarkable transcriptome changes, including increased Creb3l1 expression, to ensure that the supply of vasopressin meets demand. To determine where else Creb3l1 fits into the secretory cell supply chain, we performed RNA‐sequencing of Creb3l1 knockdown anterior pituitary mouse corticotroph cell line AtT20. The target chosen for further investigation was Pcsk1, which encodes proprotein convertase enzyme 1 (PC1/3). PC1/3 is crucial for processing of neuropeptides and peptide hormones such as pro‐opiomelanocortin (POMC), proinsulin, proglucagon, vasopressin and oxytocin. Viral manipulations in supraoptic nuclei by over‐expression of Creb3l1 increased Pcsk1, whereas Creb3l1 knockdown decreased Pcsk1 expression. In vitro promoter activity and binding studies showed that Creb3l1 was a transcription factor of the Pcsk1 gene binding directly to a G‐box motif in the promoter. In the dehydrated rat anterior pituitary, Creb3l1 and Pcsk1 expression decreased in parallel compared to control, supporting our findings from manipulations in AtT20 cells and the supraoptic nucleus. No relationship was observed between Creb3l1 and Pcsk1 expression in the neurointermediate lobe of the pituitary, indicating a different mechanism of PC1/3 synthesis by these POMC‐synthesising cells. Therefore, Creb3l1, by regulating the expression of Pcsk1, does not control the processing of POMC peptides in the intermediate ...

وصف الملف: application/pdf

الإتاحة: https://doi.org/10.1111/jne.12851Test
https://hdl.handle.net/1983/10d28188-9854-4542-aa2c-c357349af22dTest
https://research-information.bris.ac.uk/en/publications/10d28188-9854-4542-aa2c-c357349af22dTest
https://research-information.bris.ac.uk/ws/files/233004749/jne.12851.pdfTest

المؤلفون: Joep Beumer, Julia Bauzá-Martinez, Tim S. Veth, Veerle Geurts, Charelle Boot, Hannah Gilliam-Vigh, Steen S. Poulsen, Filip K. Knop, Wei Wu, Hans Clevers

المساهمون: Hubrecht Institute for Developmental Biology and Stem Cell Research

المصدر: Beumer, J, Bauzá-Martinez, J, Veth, T S, Geurts, V, Boot, C, Gilliam-Vigh, H, Poulsen, S S, Knop, F K, Wu, W & Clevers, H 2022, ' Mapping prohormone processing by proteases in human enteroendocrine cells using genetically engineered organoid models ', Proceedings of the National Academy of Sciences of the United States of America, vol. 119, no. 46, e2212057119 . https://doi.org/10.1073/pnas.2212057119Test
Proceedings of the National Academy of Sciences of the United States of America, 119(46). National Academy of Sciences

مصطلحات موضوعية: Multidisciplinary, enteroendocrine cells, Insulin/metabolism, Enteroendocrine Cells, peptidomics, Peptide Hydrolases/genetics, prohormone processing, Enteroendocrine Cells/metabolism, Organoids, intestinal organoids, Endopeptidases/metabolism, Endopeptidases, Humans, Insulin, CRISPR-Cas9, Peptide Hydrolases

الوصف: Enteroendocrine cells (EECs) secrete hormones in response to ingested nutrients to control physiological processes such as appetite and insulin release. EEC hormones are synthesized as large proproteins that undergo proteolytic processing to generate bioactive peptides. Mutations in EEC-enriched proteases are associated with endocrinopathies. Due to the relative rarity of EECs and a paucity of in vitro models, intestinal prohormone processing remains challenging to assess. Here, human gut organoids in which EECs can efficiently be induced are subjected to CRISPR-Cas9–mediated modification of EEC-expressed endopeptidase and exopeptidase genes. We employ mass spectrometry–based analyses to monitor peptide processing and identify glucagon production in intestinal EECs, stimulated upon bone morphogenic protein (BMP) signaling. We map the substrates and products of major EECs endo- and exopeptidases. Our studies provide a comprehensive description of peptide hormones produced by human EECs and define the roles of specific proteases in their generation.

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::266b5fb4e15516660a7b245ba371ce25Test
https://pubmed.ncbi.nlm.nih.gov/36343264Test

المؤلفون: J. Peter H. Burbach, Philip Grant, Anita J. C. G. M. Hellemons, Joseph A. Degiorgis, Ka Wan Li, Harish C. Pant

المصدر: Biology Open, Vol 3, Iss 1, Pp 50-58 (2013)

مصطلحات موضوعية: FMRFamide, Cephalopods, Mollusk, Stellate ganglion, Giant axon, Prohormone processing, Science, Biology (General), QH301-705.5

الوصف: Summary The giant fiber system of the squid Loligo pealei mediates the escape response and is an important neurobiological model. Here, we identified an abundant transcript in the stellate ganglion (SG) that encodes a FMRFamide precursor, and characterized FMRFamide and FI/LRF-amide peptides. To determine whether FMRFamide plays a role in the adult and hatchling giant fiber system, we studied the expression of the Fmrf gene and FMRFamide peptides. In stage 29 embryos and stage 30 hatchlings, Ffmr transcripts and FMRFamide peptide were low to undetectable in the SG, in contrast to groups of neurons intensely expressing the Fmrf gene in several brain lobes, including those that innervate the SG. In the adult SG the Fmrf gene was highly expressed, but the FMRFamide peptide was in low abundance. Intense staining for FMRFamide in the adult SG was confined to microneurons and fibers in the neuropil and to small fibers surrounding giant axons in stellar nerves. This shows that the Fmrf gene in the SG is strongly regulated post-hatching, and suggests that the FMRFamide precursor is incompletely processed in the adult SG. The data suggest that the SG only employs the Fmrf gene post-hatching and restricts the biosynthesis of FMRFamide, demonstrating that this peptide is not a major transmitter of the giant fiber system. This contrasts with brain lobes that engage FMRFamide embryonically as a regulatory peptide in multiple neuronal systems, including the afferent fibers that innervate the SG. The biological significance of these mechanisms may be to generate diversity within Fmrf-expressing systems in cephalopods.

وصف الملف: electronic resource

العلاقة: http://bio.biologists.org/content/3/1/50Test; https://doaj.org/toc/2046-6390Test

الوصول الحر: https://doaj.org/article/69f3acfbe5f74259880abc412250695cTest

المؤلفون: Michael eWeiss, Shu-Jin eChan

المصدر: Frontiers in Endocrinology, Vol 6 (2015)

مصطلحات موضوعية: Diabetes Mellitus, Proinsulin, Insulin receptor, Prohormone processing, hormone biosynthesis, Diseases of the endocrine glands. Clinical endocrinology, RC648-665

الوصف: Pioneering endocrinologist and molecular biologist Donald Frederick Steiner, A. N. Pritzker Distinguished Service Professor of Medicine and Biochemistry & Molecular Biology at the University of Chicago (Fig. 1), died on November 11, 2014 at the age of 84. Very few scientists, observed Nobel Laureate Joseph L Goldstein, M.D., Chairman of the Department of Molecular Genetics at the University of Texas (UT) Southwestern Medical Center, can lay claim to original research that has stood the test of time in both the biological and clinical arenas. Steiner’s contributions meet this dual standard. Dr. Steiner was also renowned for his mentorship of successive generations of leaders in biochemistry and academic medicine.

وصف الملف: electronic resource

العلاقة: http://journal.frontiersin.org/Journal/10.3389/fendo.2015.00057/fullTest; https://doaj.org/toc/1664-2392Test

الوصول الحر: https://doaj.org/article/3ae53b5d285a4ef6a805ccf7661215edTest

المؤلفون: Ouafik, L'Houcine, Giraud, Pierre, Salers, Paul, Dutour, Anne, Castanas, Elias, Boudouresque, Françoise, Oliver, Charles

المصدر: Proceedings of the National Academy of Sciences of the United States of America, 1987 Jan 01. 84(1), 261-264.

الوصول الحر: https://www.jstor.org/stable/28989Test

المؤلفون: Mezey, Eva, Fricker, Lloyd D., Pruss, Rebecca M., Siegel, Ruth E., Brownstein, Michael J.

المصدر: Proceedings of the National Academy of Sciences of the United States of America, 1985 Jul . 82(14), 4745-4749.

الوصول الحر: https://www.jstor.org/stable/26121Test