Browse
Submit Data
Databases
API
Help

Dataset Information

10 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

MRNA expression analysis of cell cycle genes in islets of pregnant mice.

ABSTRACT:

Aims/hypothesis

Pregnancy requires an increase in the functional beta cell mass to match metabolic needs for insulin. To understand this adaptation at the molecular level, we undertook a time course analysis of mRNA expression in mice.

Methods

Total RNA extracted from C57Bl6/J mouse islets every 3 days during pregnancy was hybridised on commercially available expression arrays. Gene network analysis was performed and changes in functional clusters over time visualised. The function of putative novel cell cycle genes was assessed via silencing in replicating mouse insulinoma 6 (MIN6) cells.

Results

Gene network analysis identified a large gene cluster associated with cell cycle control (67 genes, all upregulated by ≥ 1.5-fold, p < 0.001). The number of upregulated cell cycle genes and the mRNA expression levels of individual genes peaked at pregnancy day (P)9.5. Filtering of poorly annotated genes with enhanced expression in islets at P9.5, and in MIN6 cells and thymus resulted in further studies with G7e (also known as D17H6S56E-5) and Fignl1. Gene knock-down experiments in MIN6 cells suggested that these genes are indeed involved in adequate cell cycle accomplishment.

Conclusions/interpretation

A sharp peak of cell cycle-related mRNA expression in islets occurs around P9.5, after which beta cell replication is increased. As illustrated by the identification of G7e and Fignl1 in islets of pregnant mice, further study of this distinct transcriptional peak should help to unravel the complex process of beta cell replication.

SUBMITTER: Schraenen A

PROVIDER: S-EPMC2974927 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Expression data from islets of non-pregnant and pregnant PRLR+/+ and PRLR-/- mice

Project description:ABSTRACT:Pregnancy requires a higher functional beta cell mass and this is associated with profound changes in the gene expression profile of pancreatic islets. Taking Tph1 as a sensitive marker for pregnancy-related islet mRNA expression in female mice, we previously identified prolactin receptors and placental lactogen as key signalling molecules. Since beta cells from male mice also express prolactin receptors, the question arose whether male and female islets have the same phenotypic resilience at the mRNA level during pregnancy. We addressed this question in vitro, by using islet tissue culture with placental lactogen and in vivo, by transplanting male or female islets into female acceptor mice. Additionally, the islet mRNA expression of pregnant prolactin receptor deficient mice was compared with that of their pregnant wild-type littermates. When cultured with placental lactogen, or transplanted in female recipients that became pregnant (day 12.5), male islets induced the ‘islet pregnancy gene signature’, which we defined as the 12 highest induced genes in non-transplanted female islets at day 12.5 of pregnancy. In addition, serotonin immunoreactivity was also induced in these male transplanted islets at day 12.5 of pregnancy. In order to investigate the importance of prolactin receptors in these mRNA changes we used a prolactin receptor deficient mouse model. For the 12 genes of the signature, which are highly induced in control pregnant mice, no significant induction of mRNA transcripts was found at day 9.5 of pregnancy. Together, our results support the key role of placental lactogen as a circulating factor that can trigger the pregnancy mRNA profile in male and female beta cells.

2015-03-31 | GSE59141 | GEO

Expression data from islets of non-pregnant and pregnant PRLR+/+ and PRLR-/- mice

2015-03-31 | E-GEOD-59141 | biostudies-arrayexpress

Differential Expression of Ormdl Genes in the Islets of Mice and Humans with Obesity.

Project description:The orosomucoid-like (Ormdl) proteins play a critical role in sphingolipid homeostasis, inflammation, and ER stress, all of which are associated with obesity and βcell dysfunction. However, their roles in β cells and obesity remain unknown. Here, we show that islets from overweight/obese human donors displayed marginally reduced ORMDL1-2 expression, whereas ORMDL3 expression was significantly downregulated compared with islets from lean donors. In contrast, Ormdl3 was substantially upregulated in the islets of leptin-deficient obese (ob/ob) mice compared with lean mice. Treatment of ob/ob mice and their islets with leptin markedly reduced islet Ormld3 expression. Ormdl3 knockdown in a β cell line induced expression of pro-apoptotic markers, which was rescued by ceramide synthase inhibitor fumonisin B1. Our results reveal differential expression of Ormdl3 in the islets of a mouse model and humans with obesity, highlight the potential effect of leptin in this differential regulation, and suggest a role for Ormdl3 in β cell apoptosis.

| S-EPMC7358727 | biostudies-literature

RNA-seq of pancreatic islets from pregnant mice

Project description:During pregnancy, the energy requirements of the fetus impose changes in maternal metabolism. Increasing insulin resistance in the mother maintains nutrient flow to the growing fetus, while prolactin and placental lactogen counterbalance this resistance and prevent maternal hyperglycemia by driving expansion of the maternal population of insulin-producing beta-cells. However, the exact mechanisms by which the lactogenic hormones drive beta-cell expansion remain uncertain. Here we show that serotonin acts downstream of lactogen signaling to drive beta-cell proliferation. Serotonin synthetic enzyme Tph1 and serotonin production increased sharply in beta-cells during pregnancy or after treatment with lactogens in vitro. Inhibition of serotonin synthesis by dietary tryptophan restriction or Tph inhibition blocked beta-cell expansion and induced glucose intolerance in pregnant mice without affecting insulin sensitivity. Expression of the Gq-linked serotonin receptor Htr2b in maternal islets increased during pregnancy and normalized just prior to parturition, while expression of the Gi-linked receptor Htr1d increased at the end of pregnancy and postpartum. Blocking Htr2b signaling in pregnant mice also blocked beta-cell expansion and caused glucose intolerance. These studies reveal an integrated signaling pathway linking beta-cell mass to anticipated insulin need during pregnancy. Modulators of this pathway, including medications and diet, may affect the risk of gestational diabetes. Analysis of poly(A)+ RNA from 3 biological replicates of pancreatic islets isolated from normal female and pregnant female mice

2010-07-01 | E-GEOD-21860 | biostudies-arrayexpress

Analysis of gene expression in pancreatic islets from diet-induced obese mice.

Project description:In insulin-resistant status such as obesity, failure of pancreatic islets to increase insulin secretion leads to diabetes. We sought to screen for the islet genes that facilitate islet adaptation to obesity by comparing gene expression profiles between two strains of obesity-prone inbred mice with different propensities for hyperglycemia. C57BL/6J and AKR/J were fed regular rodent chow or high-fat diet, after which islet morphology, secretory function, and gene expression were assessed. AKR/J had lower blood glucose and higher insulin levels compared with C57BL/6J mice on regular rodent chow or high-fat diet. Insulin secretion was 3.2-fold higher in AKR/J than C57BL/6J mice following intraperitoneal glucose injection. Likewise, glucose-stimulated insulin secretion from isolated islets was higher in AKR/J. Additionally, islet mass was 1.4-fold greater in AKR/J compared with C57BL/6J. To elucidate the factors associated with the differences in islet function, we analyzed the gene expression profiles in islets in AKR/J and C57BL/6J mice. Of 14,000 genes examined, 202 were upregulated and 270 were downregulated in islets from diet-induced obese AKR/J mice compared with C57BL/6J mice. Key genes involved in islet signaling and metabolism, e.g., glucagon-like peptide-1 receptor, sterol Co-A desaturase 1 and 2, and fatty acid desaturase 2 were upregulated in obese AKR/J mice. The expression of multiple extracellular matrix proteins was also increased in AKR/J mice, suggesting a role in modulation of islet mass. Functional analyses of differentially regulated genes hold promise for elucidating factors linking obesity to alterations in islet function.

| S-EPMC2604788 | biostudies-literature

Expression data from pancreatic islets of prolactin receptor null pregnant mice

Project description:Pancreatic islets adapt to the increase in insulin demand during pregnancy by up-regulating beta cell proliferation, insulin synthesis, and lowering the threshold of glucose-stimulated insulin secretion. In vitro studies suggest that pregnancy hormones, such as placental lactogens and prolactin, both act through the prolactin receptor, are required for these adaptation. Furhtermore, we found that transgenic mice with heterogenous prolactin receptor null mutation are glucose intolerant, with a lower beta-cell mass and lower insulin levels. The goal here is to discover novel targets of prolactin receptor signaling in pancreatic beta cells during pregnancy.

2019-02-01 | GSE125350 | GEO

Expression data from islets of Pdx1-creLate, control and pregnant mice

Project description:ABSTRACT: The human growth hormone (hGH) minigene is frequently used in the derivation of transgenic mouse lines to enhance transgene expression. Although this minigene is present in the transgenes as a secondcistron, and thus not thought to be expressed, we found that three commonly used lines, Pdx1-CreLate, RIP-Cre, and MIP-GFP, each expressed significant amounts of hGH in pancreatic islets. Locally secreted hGH binds to prolactin receptors on β cells, activates STAT5 signaling, and induces pregnancy-like changes in gene expression, thereby augmenting pancreatic β cell mass and insulin content. In addition, islets of Pdx1-CreLate mice have lower GLUT2 expression and reduced glucose-induced insulin release and are protected against the β cell toxin streptozotocin. These findings may be important when interpreting results obtained when these and other hGH minigene-containing transgenic mice are used. Data obtained for the Pdx1-creLate and control samples were compaired to investigate the effect of hGH on the mRNA profile of islets. The data obtained from the islets of pregnant mice was added to the analysis to confirm the pregnacy-like phenotype in the Pdx1-creLate islets. The data of the different days of pregnancy was already described in Schraenen et al. 2010 (PMID: 20886204 and PMID: 20938637).

2014-02-14 | GSE50851 | GEO

Expression data from islets of Pdx1-creLate, control and pregnant mice

Project description:ABSTRACT: The human growth hormone (hGH) minigene is frequently used in transgenic mouse lines to ensure proper transgene expression. Here, we show that hGH is expressed in islets isolated from the commonly used Pdx1-CreLate mouse model. Locally secreted hGH activates prolactin receptors on M-NM-2 cells causing phosphorylation of STAT5, and induces a pregnancy-like change in gene expression, augmented pancreatic M-NM-2 cell mass and insulin content. In addition, islets of Pdx1-CreLate mice had lower GLUT2 expression, reduced glucose-induced insulin release and were protected against the M-NM-2 cell toxin streptozotocin. As the hGH minigene is commonly used in a great number of Cre-driver and other transgenic mouse models in diabetes research, the currently reported profound phenotypic changes may necessitate the re-evaluation of a large amount of previously published work. Data obtained for the Pdx1-creLate and control samples were compaired to investigate the effect of hGH on the mRNA profile of islets. The data obtained from the islets of pregnant mice was added to the analysis to confirm the pregnacy-like phenotype in the Pdx1-creLate islets. The data of the different days of pregnancy was already described in Schraenen et al. 2010 (PMID: 20886204 and PMID: 20938637). Islets were isolated from Pdx1-creLate, control and pregnant mice for RNA extraction and hybridization on Affymetrix microarrays. For every condition, at least 3 biological replicates were used.

2014-02-14 | E-GEOD-50851 | biostudies-arrayexpress

Enhanced Expression of the Key Mitosis Regulator Cyclin B1 Is Mediated by PDZ-Binding Kinase in Islets of Pregnant Mice.

Project description:The proliferation of pancreatic ? cells is enhanced to enable an increase in ?-cell mass and to compensate for insulin resistance during pregnancy. To elucidate the mechanisms involved, we previously investigated islets from pregnant and nonpregnant mice by gene expression profiling and found that the expression of postsynaptic density-95/Discs large/zonula occludens-1 (PDZ)-binding kinase (Pbk), a member of the mitogen-activated protein kinase kinase family, is increased in pregnant mouse islets compared with control mouse islets. Among the pregnancy hormones, treatment with estradiol upregulated Pbk expression. Inhibition of Pbk expression using a small interfering RNA for Pbk reduced bromodeoxyuridine incorporation in mouse insulinoma 6 cells, which was accompanied by a decreased expression of Ccnb1, a regulatory gene involved in mitosis. Ccnb1 expression was augmented in mouse islets during pregnancy. The forced expression of Pbk using an adenovirus system in isolated mouse islets increased Ccnb1 expression, and the Pbk inhibitor HI-TOPK-032 suppressed Ccnb1 expression in islets isolated from pregnant mice. Our results suggest that Pbk contributes to the expansion of islets during pregnancy and that Ccnb1 may assist Pbk in its role in ?-cell proliferation.

| S-EPMC5841183 | biostudies-literature

A viral microRNA down-regulates multiple cell cycle genes through mRNA 5'UTRs.

Project description:Global gene expression data combined with bioinformatic analysis provides strong evidence that mammalian miRNAs mediate repression of gene expression primarily through binding sites within the 3' untranslated region (UTR). Using RNA induced silencing complex immunoprecipitation (RISC-IP) techniques we have identified multiple cellular targets for a human cytomegalovirus (HCMV) miRNA, miR-US25-1. Strikingly, this miRNA binds target sites primarily within 5'UTRs, mediating significant reduction in gene expression. Intriguingly, many of the genes targeted by miR-US25-1 are associated with cell cycle control, including cyclin E2, BRCC3, EID1, MAPRE2, and CD147, suggesting that miR-US25-1 is targeting genes within a related pathway. Deletion of miR-US25-1 from HCMV results in over expression of cyclin E2 in the context of viral infection. Our studies demonstrate that a viral miRNA mediates translational repression of multiple cellular genes by targeting mRNA 5'UTRs.

| S-EPMC2891821 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data