Regulatory Architecture of the LβT2 Gonadotrope Cell Underlying the Response to Gonadotropin-Releasing Hormone
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA397847 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The LβT2 mouse pituitary cell line has many characteristics of a mature gonadotrope and is a widely used model system for studying developmental processes and the response to gonadotropin-releasing hormone (GnRH). The global epigenetic landscape, which contributes to cell-specific gene regulatory mechanisms, and the single-cell transcriptome response variation of LβT2 cells have not been previously investigated. Here, we integrate the transcriptome and genome-wide chromatin accessibility state of LβT2 cells during GnRH stimulation. Additionally, we examine cell-to-cell variability in the transcriptional response to GnRH using gel-in-emulsion Drop-seq technology. Analysis of a bulk RNA-seq dataset obtained 45 minutes after exposure to either GnRH or vehicle identified 112 transcripts that were regulated > 4-fold by GnRH (FDR < 0.05). The top regulated transcripts constitute, as determined by Bayesian massive public data integration analysis, a human pituitary-relevant coordinated gene program. Chromatin accessibility (ATAC-seq) datasets generated from GnRH-treated LβT2 cells identified more than 58,000 open chromatin regions, some containing notches consistent with bound transcription factor footprints. Study of the most prominent open regions showed that 75% were in transcriptionally active promoters or introns, supporting their involvement in active transcription. Lhb, Cga, and Egr1 showed significantly open chromatin over their promoters. While Fshb was closed over its promoter, several discrete significantly open regions were found at -40 to -90 kb, which may represent novel upstream enhancers. Chromatin accessibility determined by ATAC-seq was associated with high levels of gene expression determined by RNA-seq. We obtained high quality single-cell gel-in-emulsion Drop-seq transcriptome data, with an average of >4000 expressed genes/cell, from 1992 vehicle- and 1889 GnRH-treated cells. While the individual cell expression patterns showed high cell-to-cell variation, representing both biological and measurement variation, the average expression patterns correlated well with bulk RNA-seq data. Computational assignment of each cell to its precise cell cycle phase showed that the response to GnRH was unaffected by cell cycle. To our knowledge, this study represents the first genome-wide epigenetic and single-cell transcriptomic characterization of this important gonadotrope model. The data have been deposited publicly and should provide a resource for hypothesis generation and further study.
2018-02-15 | GSE102396 | GEO
Project description:The LβT2 mouse pituitary cell line has many characteristics of a mature gonadotrope and is a widely used model system for studying developmental processes and the response to gonadotropin-releasing hormone (GnRH). The global epigenetic landscape, which contributes to cell-specific gene regulatory mechanisms, and the single-cell transcriptome response variation of LβT2 cells have not been previously investigated. Here, we integrate the transcriptome and genome-wide chromatin accessibility state of LβT2 cells during GnRH stimulation. Additionally, we examine cell-to-cell variability in the transcriptional response to GnRH using gel-in-emulsion Drop-seq technology. Analysis of a bulk RNA-seq dataset obtained 45 minutes after exposure to either GnRH or vehicle identified 112 transcripts that were regulated > 4-fold by GnRH (FDR < 0.05). The top regulated transcripts constitute, as determined by Bayesian massive public data integration analysis, a human pituitary-relevant coordinated gene program. Chromatin accessibility (ATAC-seq) datasets generated from GnRH-treated LβT2 cells identified more than 58,000 open chromatin regions, some containing notches consistent with bound transcription factor footprints. Study of the most prominent open regions showed that 75% were in transcriptionally active promoters or introns, supporting their involvement in active transcription. Lhb, Cga, and Egr1 showed significantly open chromatin over their promoters. While Fshb was closed over its promoter, several discrete significantly open regions were found at -40 to -90 kb, which may represent novel upstream enhancers. Chromatin accessibility determined by ATAC-seq was associated with high levels of gene expression determined by RNA-seq. We obtained high quality single-cell gel-in-emulsion Drop-seq transcriptome data, with an average of >4000 expressed genes/cell, from 1992 vehicle- and 1889 GnRH-treated cells. While the individual cell expression patterns showed high cell-to-cell variation, representing both biological and measurement variation, the average expression patterns correlated well with bulk RNA-seq data. Computational assignment of each cell to its precise cell cycle phase showed that the response to GnRH was unaffected by cell cycle. To our knowledge, this study represents the first genome-wide epigenetic and single-cell transcriptomic characterization of this important gonadotrope model. The data have been deposited publicly and should provide a resource for hypothesis generation and further study.
2018-02-15 | GSE102479 | GEO
Project description: Not available
| S-EPMC5816955 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2018-02-15 | GSE102480 | GEO
Project description:Background: Gonadotropin-releasing hormone (GnRH) neurons play a pivotal role in regulation of the hypothalamic-pituitary gonadal axis in a sex-specific manner. We hypothesized that the differences seen in reproductive functions of males and females are associated with a sexually dimorphic gene expression profile of GnRH neurons. Methods and Results: We compared the transcriptome of GnRH neurons obtained from intact, metestrous female and male GnRH-GFP transgenic mice. About 1500 individual GnRH neurons from each sex were sampled with laser capture microdissection followed by whole transcriptome amplification for gene expression profiling. Under stringent selection criteria (fold change > 1.6, adjusted p-value 0.01), Affymetrix Mouse Genome 430 PM array analysis identified 543 differentially expressed genes. Sexual dimorphism was most apparent in gene clusters associated with synaptic communication, signal transduction, cell adhesion, vesicular transport and cell metabolism. To validate microarray results, 57 genes were selected and 91% of their differential expression was confirmed by real-time PCR. Similarly, 88% of microarray results were confirmed with PCR from independent samples obtained by patch pipette harvesting and pooling of 30 GnRH neurons from each sex. We found significant differences in expression of genes involved in vesicle priming and docking (Syt1, Cplx1), GABAergic (Gabra3, Gabrb3, Gabrg2) and glutamatergic (Gria1, Grin1, Slc17a6) neurotransmission, peptide signaling (Sstr3, Npr2, Cxcr4) and the regulation of intracellular ion homeostasis (Cacna1, Cacnb1, Cacng5, Kcnq2, Kcnc1). Conclusion: The striking sexual dimorphism of the GnRH neuron transcriptome we report here contributes to the better understanding the differences in cellular mechanisms of GnRH neurons in the two sexes.
2021-01-18 | GSE66806 | GEO
Project description: Not available
| S-EPMC2746289 | biostudies-literature
Project description: Not available
| S-EPMC5671645 | biostudies-literature
Project description:Abstract: Peptidylarginine deiminases (PADs or PADIs) catalyze the conversion of positively charged arginine to neutral citrulline, which alters target protein structure and function. It is well established that a gonadotropin releasing hormone agonist (GnRHa) stimulates PAD2-catalyzed histone citrullination to epigenetically regulate gonadotropin gene expression in the gonadotrope derived LBT2 cell line. However, PADs are also found in the cytoplasm. Given this, we used mass spectrometry to identify additional non-histone proteins that are citrullinated following GnRHa stimulation and characterize the temporal dynamics of this modification. Our results show that actin and tubulin are rapidly citrullinated, which led us to hypothesize that GnRHa might induce their citrullination to modulate cytoskeletal dynamics and architecture. Data shows that 10 nM GnRHa induces citrullination of beta-actin with maximal levels occurring at 10 minutes. The level of beta-actin citrullination is reduced in the presence of the pan-PAD inhibitor bi-phenyl-benzimidazole-Cl-amidine (BB-ClA), which also prevents GnRHa induced actin reorganization in dispersed mouse gonadotrope cells. GnRHa induces citrullination of beta-tubulin with elevated levels occurring at 30 minutes; similarly to beta-actin, this response is attenuated in the presence of BB-ClA. To examine the functional consequence of beta-tubulin citrullination, we utilized fluorescently tagged end binding protein 1 (EB1-GFP) to track the growing plus end of microtubules (MT) in real time in transfected LBT2 cells. Time-lapse confocal microscopy of EB1-GFP reveals that MT average lifetime increases following 30 minutes of GnRHa treatment, but this increase is attenuated by PAD inhibition. Taken together, our data suggest that GnRHa induced citrullination alters actin reorganization and MT lifetime in gonadotrope cells.
Keywords: gonadotrope, peptidylarginine deiminase, citrullination, cytoskeleton, beta tubulin, beta actin, microtubules
2024-01-31 | MSV000093973 | MassIVE
Project description: Not available
| S-EPMC4547917 | biostudies-literature
Project description:Background: The exact nature of the interrelationship between pubertal brain development and hormones involvement has always attracted wide interest. Brain structural changes that occur during the pubertal developmental process mainly appear in the regions most closely linked with emotion, motivation and cognitive functions. Using a sheep model, we have previously shown that peri-pubertal pharmacological blockade of gonadotropin-releasing hormone (GnRH) receptors results in increased sex-differences in cognitive executive function and emotional control, as well as in a sex- and side-specific gene expression pattern of hippocampal genes associated with synaptic plasticity and endocrine signaling. In this study, we explore the effects of this treatment regime on the amygdalar gene expression profile. Methods: The study was conducted with 30 same-sex twin lambs (14 female and 16 male), half of which were treated with the GnRH agonist (GnRHa) goserelin acetate every 4th week, beginning before puberty, until 50 weeks of age. The gene expression profiles of left and right amygdala samples from all 30 animals were measured by using ovine 8 X 15 K Agilent microarrays. Furthermore, differential expression of a selected number of genes was confirmed by qRT-PCR (Quantitative real time PCR). Networking analyses and Gene Ontology (GO) Term analyses were performed with the Ingenuity Pathway Analysis (IPA), version 7.5 DAVID (Database for Annotation, Visualization and integrated Discovery) software packages respectively. Results: GnRHa treatment was associated with significant sex- and hemisphere-specific differential expression of genes. Interestingly, genome-wide transcription showed a set of 438 (p value <0.05) genes in female treated left and 46 (p value <0.0.5) genes in females treated right amygdala were differentially expressed but not in any treatment group of male animals. Conclusion: Our results indicate that GnRH directly and/or indirectly is involved in the regulation of sex- and side-specific differential expression of genes in amygdala. Hence, this finding should be considered when long-term peri-pubertal GnRHa treatment is used in children.
2013-05-31 | GSE44202 | GEO