Project description:Nucleoredoxin (Nxn) encodes a multi-functional enzyme with oxidoreductase activity that regulates many different signaling pathways in a redox-dependent manner. It is involved in a variety of cellular processes. Rare NXN mutations are reported in some individuals with recessive Robinow syndrome, which involves mesomelic short stature, craniofacial dysmorphisms, and incompletely penetrant heart and palate defects. Here we report that Nxn is expressed in the ventral diencephalon and Rathke’s pouch, and that Nxn deficient mice have pituitary dysmorphology, cleft palate, and craniofacial abnormalities. Nxn mutant mice exhibit altered WNT signaling and reduced progression of pituitary stem cells to hormone-producing cells. These results suggest that some patients with Robinow syndrome may have pituitary insufficiency and benefit from evaluation by endocrinologists.
Project description:Transcription factors and signaling pathways that regulate stem cells and specialized hormone-producing cells in the pituitary gland have been the subject of intense study and have yielded a mechanistic understanding of pituitary organogenesis and disease. Yet, the regulation of stem cell proliferation and differentiation, the heterogeneity among specialized hormone-producing cells, and the role of non-endocrine cells in the gland remain important, unanswered questions. Recent advances in single-cell RNA sequencing (scRNAseq) technologies provide new avenues to address these questions. We performed scRNAseq on approximately 13,663 cells pooled from six whole pituitary glands of 7-week-old C57BL/6 male mice. We identified pituitary endocrine and stem cells in silico, as well as other support cell-types such as endothelia, connective tissue, and red and white blood cells. Differential gene expression analyses identify known and novel markers of pituitary endocrine and stem cell populations. We demonstrate the value of scRNAseq by in vivo validation of a novel gonadotrope-enriched marker, Foxp2. We present novel scRNAseq data of in vivo pituitary tissue, including data from agnostic clustering algorithms which suggest the presence of a somatotrope subpopulation enriched in sterol/cholesterol synthesis genes. At the same time, we show that incomplete transcriptome annotation can cause false negatives on some scRNAseq platforms that only generate 3’ transcript end sequences, and use in vivo data to recover reads of the pituitary transcription factor Prop1. Ultimately, scRNAseq technologies represent a significant opportunity to address longstanding questions regarding the development and function of the different populations of the pituitary gland throughout life.
Project description:Gene alteration analysis on 121 GH-producing pituitary adenomas and non-target proteomics analysis with RNA sequencing analysis on 45 non-functioning pituitary adenomas (NFPAs) and 60 growth hormone (GH)-producing pituitary adenomas were performed, and integrated these results with the clinical characteristics of acromegaly. We attempted to identify key players involved in shaping the clinical features of acromegaly, especially those related to treatment efficacy. This project revealed the importance of GNAS mutations in terms of clinical and biochemical characteristics and identified novel molecules that may be involved in the responsiveness to medical treatment.
Project description:We profiled the somatic landscape of 21 growth hormone (GH) -secreting pituitary adenomas using somatic copy-number alteration (SCNA), whole-genome sequencing (WGS), bisulfate sequencing, and transcriptome approaches. See details in Valimaki et al. Genetic and epigenetic characterization of growth hormone (GH) - secreting pituitary tumors. Manuscript in preparation, 2019.
Project description:The clinical characteristics of growth hormone (GH)-producing pituitary adenomas vary across patients. In this study, we aimed to integrate the genetic alterations, protein expression profiles, transcriptomes, and clinical characteristics of GH-producing pituitary adenomas to detect molecules associated with acromegaly characteristics. Targeted capture sequencing and copy number analysis of 36 genes and non-targeted proteomics analysis were performed on fresh-frozen samples from 121 sporadic GH-producing pituitary adenomas. Targeted capture sequencing revealed GNAS as the only driver gene, as previously reported. Classification by consensus clustering using both RNA sequencing and proteomics revealed many similarities between the proteome and the transcriptome. Gene ontology analysis was performed for differentially expressed proteins between wild-type and mutant GNAS samples identified by non-targeted proteomics analysis and involved in G protein–coupled receptor (GPCR) pathways. The results suggested that GNAS mutations impact endocrinological features in acromegaly through GPCR pathway induction. ATP2A2 and ARID5B correlated with the GH change rate in the octreotide loading test, and WWC3, SERINC1, and ZFAND3 correlated with the tumor volume change rate after somatostatin analog treatment. These results identified a biological connection between GNAS mutations and the clinical and biochemical characteristics of acromegaly, revealing novel molecules associated with acromegaly that may affect medical treatment efficacy.
Project description:The pituitary is the vertebrate endocrine gland responsible for the production and secretion of several essential peptide hormones. These, in turn, control many aspects of an animal’s physiology and development, including growth, reproduction, homeostasis, metabolism and stress responses. In teleost fish, each hormone is presumably produced by a specific cell type. However, key details on the regulation of, and communication between these cell types are still poorly understood. We have therefore generated gene expression profiles for 2592 and 3804 individual cells from the pituitaries of female and male adult medaka (Oryzias latipes), respectively. Based on expression profile clustering, we define 15 and 16 distinct cell types in the female and male pituitary, respectively, of which nine are involved in the exclusive production of a single peptide hormone. Collectively, our data provide a high-quality reference for studies on pituitary biology and the regulation of hormone production, both in fish and in vertebrates in general.
Project description:Data from 12 fresh-frozen somatotropinomas and their corresponding blood samples. Details are given in Valimaki et al. Whole-genome sequencing of Growth Hormone (GH) -secreting Pituitary Adenoma. Provisionally accepted, 2015.
Project description:The anterior pituitary gland plays central roles in body growth, reproduction, metabolism and the stress response. In this study, we performed single-cell RNA-sequencing (scRNA-seq) of 4,113 individual cells from human fetal pituitaries. We characterized divergent developmental trajectories with distinct transitional intermediate states in five hormone-producing cell lineages. Furthermore, we characterized the cellular heterogeneity of pituitary stem cells, identifying a hybrid epithelial/mesenchymal state and an early-to-late state transition. These analyses define a single-cell resolution roadmap for human pituitary development.
Project description:Inter-organ communication is a major hallmark of health and is often orchestrated by hormones released by the anterior pituitary gland. Pituitary gonadotropes secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH) to regulate gonadal function and control fertility. Whether FSH and LH also act on organs other than the gonads is debated. Here, we found that gonadotrope depletion in adult female mice triggers profound hypogonadism, obesity, glucose intolerance, fatty liver, and bone loss. The absence of sex steroids precipitates these phenotypes, with the notable exception of fatty liver, which results from ovary-independent actions of FSH. We uncover paracrine FSH action on pituitary corticotropes as a novel mechanism to restrain the production of corticosterone and prevent hepatic steatosis. Our data demonstrate that functional communication of two distinct hormone-secreting cell populations in the pituitary regulates hepatic lipid metabolism.
Project description:Understanding of physiology and pathology of an organ composed of variety of cell populations depends critically on genome-wide information on each cell type. Here, we report single-cell transcriptome profiling of over 6800 freshly dispersed anterior pituitary cells from postpubertal male and female rats. Six pituitary-specific cell types were identified based on known marker genes and characterized: folliculostellate cells and hormone producing corticotrophs, gonadotrophs, thyrotrophs, somatotrophs, and lactotrophs. Also identified were endothelial and blood cells from the pituitary capillary network. The expression of numerous developmental and neuroendocrine marker genes in both folliculostellate and hormone producing cells supports that they have a common origin. For several genes, the validity of transcriptome analysis was confirmed by qRT-PCR and single cell immunocytochemistry. Folliculostellate cells exhibit impressive transcriptome diversity, indicating their major roles in production of endogenous ligands and detoxification enzymes, and organization of extracellular matrix. Transcriptome profiles of hormone producing cells also indicate contributions toward those functions, while also clearly demonstrating their endocrine function. This survey highlights many novel genetic markers contributing to pituitary cell type identity, sexual dimorphism, and function and points to relationships between hormone producing and folliculostellate cells.