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Roisman-Geller N, Pisanty O, Weinberger A, Gajbhiye DS, Golan M, Gothilf Y. Combined Pituitary Hormone Deficiency in lhx4-Knockout Zebrafish. Int J Mol Sci 2024; 25:7332. [PMID: 39000439 PMCID: PMC11242037 DOI: 10.3390/ijms25137332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Revised: 06/27/2024] [Accepted: 07/01/2024] [Indexed: 07/16/2024] Open
Abstract
LIM homeobox 4 (LHX4) is a transcription factor crucial for anterior pituitary (AP) development. Patients with LHX4 mutation suffer from combined pituitary hormone deficiency (CPHD), short statures, reproductive and metabolic disorders and lethality in some cases. Lhx4-knockout (KO) mice fail to develop a normal AP and die shortly after birth. Here, we characterize a zebrafish lhx4-KO model to further investigate the importance of LHX4 in pituitary gland development and regulation. At the embryonic and larval stages, these fish express lower levels of tshb mRNA compared with their wildtype siblings. In adult lhx4-KO fish, the expressions of pituitary hormone-encoding transcripts, including growth hormone (gh), thyroid stimulating hormone (tshb), proopiomelanocortin (pomca) and follicle stimulating hormone (fshb), are reduced, the pomca promoter-driven expression in corticotrophs is dampened and luteinizing hormone (lhb)-producing gonadotrophs are severely depleted. In contrast to Lhx4-KO mice, Lhx4-deficient fish survive to adulthood, but with a reduced body size. Importantly, lhx4-KO males reach sexual maturity and are reproductively competent, whereas the females remain infertile with undeveloped ovaries. These phenotypes, which are reminiscent of those observed in CPHD patients, along with the advantages of the zebrafish for developmental genetics research, make this lhx4-KO fish an ideal vertebrate model to study the outcomes of LHX4 mutation.
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Affiliation(s)
- Nicole Roisman-Geller
- School of Neurobiology, Biochemistry and Biophysics, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel; (N.R.-G.); (O.P.); (A.W.)
| | - Odelia Pisanty
- School of Neurobiology, Biochemistry and Biophysics, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel; (N.R.-G.); (O.P.); (A.W.)
| | - Alon Weinberger
- School of Neurobiology, Biochemistry and Biophysics, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel; (N.R.-G.); (O.P.); (A.W.)
| | - Deodatta S. Gajbhiye
- Department of Poultry and Aquaculture, Institute of Animal Sciences, Agricultural Research Organization, Volcani Center, Rishon Letziyon 7505101, Israel; (D.S.G.); (M.G.)
| | - Matan Golan
- Department of Poultry and Aquaculture, Institute of Animal Sciences, Agricultural Research Organization, Volcani Center, Rishon Letziyon 7505101, Israel; (D.S.G.); (M.G.)
| | - Yoav Gothilf
- School of Neurobiology, Biochemistry and Biophysics, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 6997801, Israel; (N.R.-G.); (O.P.); (A.W.)
- Sagol School of Neuroscience, Tel-Aviv University, Tel-Aviv 6997801, Israel
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Wang X, Tang H, Bie Z, Wang Y, Yuan R, Zhang Z, Xiong Z, Yang Z, Bi Z, Wang B, Liu P. Clinical and Pathological Features of Pit1/SF1 Multilineage Pituitary Neuroendocrine Tumor. Neurosurgery 2024:00006123-990000000-01033. [PMID: 38289085 DOI: 10.1227/neu.0000000000002846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 12/11/2023] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Lineage-based classification has critical clinical implications in pituitary neuroendocrine tumor (PitNET). As the most prevalent subtype of multilineage PitNET, PitNET originating from both pituitary-specific positive transcription factor 1 (Pit1) and steroidogenic factor-1 (SF1) lineages (Pit1/SF1-adenoma) is expected to exhibit rich and varied clinical behaviors. A comprehensive understanding of the clinical and pathological characteristics of Pit1/SF1-adenoma will provide mechanistic insight and influence the prognosis and treatment of PitNET. METHODS A retrospective study was conducted by reviewing 57 cases of Pit1/SF1-adenoma between 2018 and 2022. We also included 88 cases of PitNET arising from Pit1 cell lineage (Pit1-adenoma) and 70 cases of PitNET arising from SF1 cell lineage (SF1-adenoma) as controls. Comprehensive data, including demographic, symptom, endocrinal, radiological, surgical, pathological, and prognostic information, were systematically collected. All specimens were immunostained for pituitary transcription factors (PTFs) and pituitary hormones. RESULTS The detection rate was 8.0% for Pit1/SF1-adenoma within PitNET surgical specimens. Pit1/SF1-adenoma displayed a male predominance, with the mean diagnosis age falling between Pit1-adenoma and SF1-adenoma. The endocrine activity of Pit1/SF1-adenoma was lower than Pit1-adenoma but higher than SF1-adenoma. Pit1/SF1-adenoma had a higher incidence of cavernous sinus invasion (56.1%) than both Pit1-adenoma (38.6%, P = .039) and SF1-adenoma (27.1%, P = .001). Furthermore, Pit1/SF1-adenoma showed more postoperative complications than Pit1-adenoma (29.8% vs 8.0%, P = .001). Nonfunctional Pit1/SF1-adenoma had a higher radiological tumor recurrence rate than nonfunctional SF1-adenoma (34.8% vs 10.9%, P = .021). Notably, the immunostaining pattern was diverse in Pit1/SF1-adenoma, with various combinations of staining intensity for PTFs and 15 combinations for 6 pituitary hormones. Intriguingly, various PTFs combinations had no different impact on the outcome of Pit1/SF1-adenoma. CONCLUSION Pit1/SF1-adenoma represents a unique pathological subtype of PitNET, characterized by distinctive clinical behaviors. Identifying Pit1/SF1-adenoma can facilitate more precise management of PitNET by the practical use of Pit1/SF1 immunostaining.
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Affiliation(s)
- Xingchao Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
| | - Hanlu Tang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
| | - Zhixu Bie
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
| | - Ying Wang
- Department of Neural Reconstruction, Beijing Neurosurgery Institute, Capital Medical University, Beijing , China
| | - Ruofei Yuan
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
| | - Zhe Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
| | - Zhixia Xiong
- Department of Pathology, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
| | - Zhijun Yang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
| | - Zhiyong Bi
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
| | - Bo Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
| | - Pinan Liu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing , China
- Department of Neural Reconstruction, Beijing Neurosurgery Institute, Capital Medical University, Beijing , China
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Ewe CK, Sommermann EM, Kenchel J, Flowers SE, Maduro MF, Joshi PM, Rothman JH. Feedforward regulatory logic controls the specification-to-differentiation transition and terminal cell fate during Caenorhabditis elegans endoderm development. Development 2022; 149:dev200337. [PMID: 35758255 PMCID: PMC10656426 DOI: 10.1242/dev.200337] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 05/13/2022] [Indexed: 11/20/2023]
Abstract
The architecture of gene regulatory networks determines the specificity and fidelity of developmental outcomes. We report that the core regulatory circuitry for endoderm development in Caenorhabditis elegans operates through a transcriptional cascade consisting of six sequentially expressed GATA-type factors that act in a recursive series of interlocked feedforward modules. This structure results in sequential redundancy, in which removal of a single factor or multiple alternate factors in the cascade leads to a mild or no effect on gut development, whereas elimination of any two sequential factors invariably causes a strong phenotype. The phenotypic strength is successfully predicted with a computational model based on the timing and levels of transcriptional states. We found that one factor in the middle of the cascade, END-1, which straddles the distinct events of specification and differentiation, functions in both processes. Finally, we reveal roles for key GATA factors in establishing spatial regulatory state domains by repressing other fates, thereby defining boundaries in the digestive tract. Our findings provide a paradigm that could account for the genetic redundancy observed in many developmental regulatory systems.
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Affiliation(s)
- Chee Kiang Ewe
- Department of MCD Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Erica M. Sommermann
- Department of MCD Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Josh Kenchel
- Program in Biomolecular Science and Engineering, University of California Santa Barbara, Santa Barbara, CA 93106, USA
- Chemical and Biomolecular Engineering Department, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Sagen E. Flowers
- Department of MCD Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Morris F. Maduro
- Molecular, Cell and Systems Biology Department, University of California Riverside, Riverside, CA 92521, USA
| | - Pradeep M. Joshi
- Department of MCD Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Joel H. Rothman
- Department of MCD Biology and Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA 93106, USA
- Program in Biomolecular Science and Engineering, University of California Santa Barbara, Santa Barbara, CA 93106, USA
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Hong SW, Kim SH, Lim SH, Lee EJ, Kim SH, Ku CR, Kim EH. Clinical Relevance of New World Health Organization Classification System for Pituitary Adenomas: A Validation Study With 2-Year Experience. Front Oncol 2021; 11:739290. [PMID: 34589436 PMCID: PMC8476031 DOI: 10.3389/fonc.2021.739290] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Accepted: 08/23/2021] [Indexed: 12/28/2022] Open
Abstract
Background The new World Health Organization (WHO) classification system proposed a cell lineage-based classification scheme for pituitary adenomas in which transcription factors (TFs) play a major role as key classifiers. We aimed to evaluate clinical relevance of the new classification system in a clinical setting. Methods TF staining was retrospectively performed for 153 clinically and histologically well characterized pituitary adenomas. Then, 484 pituitary adenomas were prospectively stained for TFs and then for relevant pituitary hormones. TF and hormone stain-based diagnoses were compared, and differences in clinical manifestations were evaluated. Results The accuracies of antibodies for three TFs were successfully validated and had an overall matching rate was 89.6%. We identified 50 (10.4%) cases with discrepancies between TF and pituitary hormone stains. Gonadotroph adenomas lacking follicle-stimulating hormone and luteinizing hormone stains account for most discrepancies. Null cell adenomas may be more prevalent than reported and may be clinically more aggressive than gonadotroph adenomas. Conclusion The new WHO classification is mostly well matched with the traditional classification. However, until the new classification is further validated and interpreted in the context of long-term clinical outcomes, routine histological examination should include full slate of immunostains for pituitary hormones as well as TFs.
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Affiliation(s)
- Seung Woo Hong
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Se Hoon Kim
- Department of Pathology, Yonsei University College of Medicine, Seoul, South Korea.,Pituitary Tumor Center, Severance Hospital, Seoul, South Korea
| | - Seung Hoon Lim
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea
| | - Eun Jig Lee
- Pituitary Tumor Center, Severance Hospital, Seoul, South Korea.,Yonsei Endocrine Research Institute, Yonsei University College of Medicine, Seoul, South Korea.,Division of Endocrinology and Metabolism, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - Sun Ho Kim
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea.,Department of Neurosurgery, Ewha Woman's University College of Medicine, Seoul, South Korea
| | - Cheol Ryong Ku
- Pituitary Tumor Center, Severance Hospital, Seoul, South Korea.,Yonsei Endocrine Research Institute, Yonsei University College of Medicine, Seoul, South Korea.,Division of Endocrinology and Metabolism, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - Eui Hyun Kim
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, South Korea.,Pituitary Tumor Center, Severance Hospital, Seoul, South Korea.,Yonsei Endocrine Research Institute, Yonsei University College of Medicine, Seoul, South Korea
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Recent advances in proteomics and its implications in pituitary endocrine disorders. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2021; 1869:140700. [PMID: 34303023 DOI: 10.1016/j.bbapap.2021.140700] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 07/03/2021] [Accepted: 07/15/2021] [Indexed: 12/15/2022]
Abstract
Pituitary adenoma is considered as one of the most frequent intracranial tumors having salient impact on human health such as mass effects, hypopituitarism and visual defects etc. During the past few decades, there has been enormous advancement in mass spectrometry (MS)-based proteomics. However, very little is known about the molecular pathogenesis of pituitary adenomas in the context of proteomics. In this review article, we have focused on the provenance of pituitary tumors and their pathogenesis with the help of MS-based proteomics approaches. Recent advancements in quantitative proteomic approaches are outlined here that would be useful in the near pituitary adenoma proteomics research. This review discusses the enormous potential of pituitary adenomas research through proteomics with a common aim of deciphering disease pathobiology and identifying the work done in studying pituitary tumors during past decade.
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Abstract
The 2017 (fourth edition) World Health Organization Classification of Endocrine Tumors has recommended major changes in classification of tumors of the pituitary gland and region. In addition to the accurate tumor subtyping, assessment of the tumor proliferative potential (mitotic and/or Ki-67 index) and other clinical parameters such as tumor invasion is strongly recommended in individual cases for consideration of clinically aggressive adenomas. It is expected that this new WHO classification will establish more uniform biologically and clinically groups of pituitary tumors and contribute to understanding of clinical outcomes for patients harboring pituitary tumors.
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Affiliation(s)
- M Beatriz S Lopes
- Department of Pathology, University of Virginia School of Medicine, 1215 Lee Street - Room 3060-HEP, Charlottesville, VA 22908-0214, USA.
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Hibara A, Yamaguchi T, Kojima M, Yamano Y, Higuchi M. Nicotine inhibits expression of Prrx1 in pituitary stem/progenitor cells through epigenetic regulation, leading to a delayed supply of growth-hormone-producing cells. Growth Horm IGF Res 2020; 51:65-74. [PMID: 32146343 DOI: 10.1016/j.ghir.2020.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 12/27/2019] [Accepted: 02/17/2020] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Nicotine, a toxic component of smoking, adversely affects animal growth and reproduction by decreasing secretion of anterior pituitary hormones. However, it has not been clarified whether nicotine inhibits the supply of endocrine cells in the pituitary gland. The present study investigated short- and long-term effects of persistent nicotine exposure on the pituitary glands of young animals. DESIGN Three-week-old male Wistar rats were exposed to nicotine (1 mg/kg body weight/day) for 7 days, and gene expression, cell numbers, and DNA methylation status were analyzed on the following day and 4 weeks after final treatments. RESULTS The expression level of the stem cell marker Sox2 was not changed by nicotine exposure throughout the experiment. On the other hand, nicotine inhibited expression of a progenitor cell marker, Prrx1, and growth hormone (Gh). Immunohistochemical analysis showed that the SOX2-positive cells positive for PRRX1 in nicotine-treated groups decreased to 61% (4-week-old) and 70% (8-week-old) of the saline-treated controls. In addition, the proportion of GH-positive cells in nicotine-treated group was 14% lower than that of saline-treated controls. Furthermore, first intron hypermethylation of Prrx1 was detected by a bisulfite sequence of genomic DNA from the anterior lobe of the rat pituitary gland. CONCLUSIONS We show that persistent nicotine exposure in young animals inhibits expression of Prrx1 in pituitary stem/progenitor cells through epigenetic regulation, leading to a delayed supply of GH-producing cells.
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Affiliation(s)
- Ayaka Hibara
- Laboratory of Veterinary Biochemistry, Joint Department of Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-minami, Tottori-shi, Tottori 680-8553, Japan
| | - Takahiro Yamaguchi
- Laboratory of Veterinary Biochemistry, Joint Department of Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-minami, Tottori-shi, Tottori 680-8553, Japan
| | - Miki Kojima
- Laboratory of Veterinary Biochemistry, Joint Department of Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-minami, Tottori-shi, Tottori 680-8553, Japan
| | - Yoshiaki Yamano
- Laboratory of Veterinary Biochemistry, Joint Department of Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-minami, Tottori-shi, Tottori 680-8553, Japan
| | - Masashi Higuchi
- Laboratory of Veterinary Biochemistry, Joint Department of Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-minami, Tottori-shi, Tottori 680-8553, Japan.
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The 2017 World Health Organization classification of tumors of the pituitary gland: a summary. Acta Neuropathol 2017; 134:521-535. [PMID: 28821944 DOI: 10.1007/s00401-017-1769-8] [Citation(s) in RCA: 341] [Impact Index Per Article: 48.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/14/2017] [Accepted: 08/15/2017] [Indexed: 12/12/2022]
Abstract
The 4th edition of the World Health Organization (WHO) classification of endocrine tumors has been recently released. In this new edition, major changes are recommended in several areas of the classification of tumors of the anterior pituitary gland (adenophypophysis). The scope of the present manuscript is to summarize these recommended changes, emphasizing a few significant topics. These changes include the following: (1) a novel approach for classifying pituitary neuroendocrine tumors according to pituitary adenohypophyseal cell lineages; (2) changes to the histological grading of pituitary neuroendocrine tumors with the elimination of the term "atypical adenoma;" and (3) introduction of new entities like the pituitary blastoma and re-definition of old entities like the null-cell adenoma. This new classification is very practical and mostly based on immunohistochemistry for pituitary hormones, pituitary-specific transcription factors, and other immunohistochemical markers commonly used in pathology practice, not requiring routine ultrastructural analysis of the tumors. Evaluation of tumor proliferation potential, by mitotic count and Ki-67 labeling index, and tumor invasion is strongly recommended on individual case basis to identify clinically aggressive adenomas. In addition, the classification offers the treating clinical team information on tumor prognosis by identifying specific variants of adenomas associated with an elevated risk for recurrence. Changes in the classification of non-neuroendocrine tumors are also proposed, in particular those tumors arising in the posterior pituitary including pituicytoma, granular cell tumor of the posterior pituitary, and spindle cell oncocytoma. These changes endorse those previously published in the 2016 WHO classification of CNS tumors. Other tumors arising in the sellar region are also reviewed in detail including craniopharyngiomas, mesenchymal and stromal tumors, germ cell tumors, and hematopoietic tumors. It is hoped that the 2017 WHO classification of pituitary tumors will establish more biologically and clinically uniform groups of tumors, make it possible for practicing pathologists to better diagnose these tumors, and contribute to our understanding of clinical outcomes for patients harboring pituitary tumors.
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S100β-Positive Cells of Mesenchymal Origin Reside in the Anterior Lobe of the Embryonic Pituitary Gland. PLoS One 2016; 11:e0163981. [PMID: 27695124 PMCID: PMC5047643 DOI: 10.1371/journal.pone.0163981] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/16/2016] [Indexed: 01/15/2023] Open
Abstract
The anterior and intermediate lobes of the pituitary gland develop through invagination of the oral ectoderm and as they are endocrine tissues, they participate in the maintenance of vital functions via the synthesis and secretion of numerous hormones. We recently observed that several extrapituitary cells invade the anterior lobe of the developing pituitary gland. This raised the question of the origin(s) of these S100β-positive cells, which are not classic endocrine cells but instead comprise a heterogeneous cell population with plural roles, especially as stem/progenitor cells. To better understand the roles of these S100β-positive cells, we performed immunohistochemical analysis using several markers in S100β/GFP-TG rats, which express GFP in S100β-expressing cells under control of the S100β promoter. GFP-positive cells were present as mesenchymal cells surrounding the developing pituitary gland and at Atwell's recess but were not present in the anterior lobe on embryonic day 15.5. These cells were negative for SOX2, a pituitary stem/progenitor marker, and PRRX1, a mesenchyme and pituitary stem/progenitor marker. However, three days later, GFP-positive and PRRX1-positive (but SOX2-negative) cells were observed in the parenchyma of the anterior lobe. Furthermore, some GFP-positive cells were positive for vimentin, p75, isolectin B4, DESMIN, and Ki67. These data suggest that S100β-positive cells of extrapituitary origin invade the anterior lobe, undergoing proliferation and diverse transformation during pituitary organogenesis.
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Wang H, Hastings R, Miller WL, Kumar TR. Fshb-iCre mice are efficient and specific Cre deleters for the gonadotrope lineage. Mol Cell Endocrinol 2016; 419:124-38. [PMID: 26472536 PMCID: PMC4684453 DOI: 10.1016/j.mce.2015.10.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 10/06/2015] [Accepted: 10/07/2015] [Indexed: 02/06/2023]
Abstract
Genetic analysis of development and function of the gonadotrope cell lineage within mouse anterior pituitary has been greatly facilitated by at least three currently available Cre strains in which Cre was either knocked into the Gnrhr locus or expressed as a transgene from Cga and Lhb promoters. However, in each case there are some limitations including CRE expression in thyrotropes within pituitary or ectopic expression outside of pituitary, for example in some populations of neurons or gonads. Hence, these Cre strains often pose problems with regard to undesirable deletion of alleles in non-gonadotrope cells, fertility and germline transmission of mutant alleles. Here, we describe generation and characterization of a new Fshb-iCre deleter strain using 4.7 kb of ovine Fshb promoter regulatory sequences driving iCre expression exclusively in the gonadotrope lineage within anterior pituitary. Fshb-iCre mice develop normally, display no ectopic CRE expression in gonads and are fertile. When crossed onto a loxP recombination-mediated red to green color switch reporter mouse genetic background, in vivo CRE recombinase activity is detectable in gonadotropes at more than 95% efficiency and the GFP-tagged gonadotropes readily purified by fluorescence activated cell sorting. We demonstrate the applicability of this Fshb-iCre deleter strain in a mouse model in which Dicer is efficiently and selectively deleted in gonadotropes. We further show that loss of DICER-dependent miRNAs in gonadotropes leads to profound suppression of gonadotropins resulting in male and female infertility. Thus, Fshb-iCre mice serve as a new genetic tool to efficiently manipulate gonadotrope-specific gene expression in vivo.
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Affiliation(s)
- Huizhen Wang
- Department of Molecular and Integrative Physiology
| | | | - William L Miller
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, 27695, USA
| | - T Rajendra Kumar
- Department of Molecular and Integrative Physiology; Center for Reproductive Sciences, Institute for Reproductive Health and Regenerative Medicine; Department of Pathology and Laboratory Medicine; Department of Neurosurgery, University of Kansas Medical Center, Kansas City, KS, 66160, USA.
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Goto M, Hojo M, Ando M, Kita A, Kitagawa M, Ohtsuka T, Kageyama R, Miyamoto S. Hes1 and Hes5 are required for differentiation of pituicytes and formation of the neurohypophysis in pituitary development. Brain Res 2015; 1625:206-17. [PMID: 26348989 DOI: 10.1016/j.brainres.2015.08.045] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 08/28/2015] [Accepted: 08/31/2015] [Indexed: 12/11/2022]
Abstract
The pituitary gland is a critical endocrine organ regulating diverse physiological functions, including homeostasis, metabolism, reproduction, and growth. It is composed of two distinct entities: the adenohypophysis, including the anterior and intermediate lobes, and the neurohypophysis known as the posterior lobe. The neurohypophysis is composed of pituicytes (glial cells) and axons projected from hypothalamic neurons. The adenohypophysis derives from Rathke's pouch, whereas the neurohypophysis derives from the infundibulum, an evagination of the ventral diencephalon. Molecular mechanisms of adenohypophysis development are much better understood, but little is known about mechanisms that regulate neurohypophysis development. Hes genes, known as Notch effectors, play a crucial role in specifying cellular fates during the development of various tissues and organs. Here, we report that the ventral diencephalon fails to evaginate resulting in complete loss of the posterior pituitary lobe in Hes1(-/-); Hes5(+/-) mutant embryos. In these mutant mice, progenitor cells are differentiated into neurons at the expense of pituicytes in the ventral diencephalon. In the developing neurohypophysis, the proliferative zone is located at the base of the infundibulum. Thus, Hes1 and Hes5 modulate not only maintenance of progenitor cells but also pituicyte versus neuron fate specification during neurohypophysis development.
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Affiliation(s)
- Masanori Goto
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan; Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Masato Hojo
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan; Department of Neurosurgery, Shiga Medical Center for Adults, 5-4-30 Moriyama, Moriyama, Shiga 524-8524, Japan.
| | - Mitsushige Ando
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan; Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Aya Kita
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan; Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Masashi Kitagawa
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan; Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Toshiyuki Ohtsuka
- Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Ryoichiro Kageyama
- Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Susumu Miyamoto
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
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14
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PRRX1- and PRRX2-positive mesenchymal stem/progenitor cells are involved in vasculogenesis during rat embryonic pituitary development. Cell Tissue Res 2015; 361:557-65. [PMID: 25795141 DOI: 10.1007/s00441-015-2128-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 01/13/2015] [Indexed: 10/23/2022]
Abstract
We have recently shown that cells positive for the paired-related homeobox transcription factors PRRX1 and PRRX2 occur in the rat pituitary, and that they are derived from two different origins: pituitary-derived cells positive for stem cell marker SOX2 and extra-pituitary-derived cells negative for SOX2. In this study, we have further characterized the PRRX1- and PRRX2-positive cells that originate from extra-pituitary cells. Immunohistochemical analyses were performed with specific antibodies against PRRX1 and PRRX2 in order to clarify their roles in pituitary vasculogenesis. PRRX1- and PRRX2-positive cells were found in Atwell's recess and at the periphery of the pituitary on embryonic day 15.5 (E15.5). Several PRRX1-positive cells then invaded the anterior lobe, together with a few PRRX2-positive cells, on E16.5. Some PRRX1-positive cells were also positive for mesenchymal stem cell marker NESTIN. Moreover, some PRRX1/NESTIN double-positive cells showed characteristics of vascular endothelial cells with an Isolectin-B4-binding capacity. PRRX1 co-localized with vascular smooth muscle cell/pericyte marker α-smooth muscle actin in the deep area of Atwell's recess. We confirmed the presence of PRRX2/NESTIN double-positive cells at an entry area in Atwell's recess and at the periphery of the pituitary, but PRRX2 did not co-localize with Isolectin B4 or α-smooth muscle actin. These data suggest that PRRX1- and PRRX2-positive mesenchymal stem/progenitor cells are present at the periphery of the embryonic pituitary and at the entry from Atwell's recess and participate in pituitary vasculogenesis by differentiation into vascular endothelial cells and pericytes, whereas the presence of PRRX2 indicates much higher stemness than PRRX1.
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Ueharu H, Higuchi M, Nishimura N, Yoshida S, Shibuya S, Sensui K, Kato T, Kato Y. Expression of Krüppel-like factor 6, KLF6, in rat pituitary stem/progenitor cells and its regulation of the PRRX2 gene. J Reprod Dev 2014; 60:304-11. [PMID: 24881871 PMCID: PMC4139505 DOI: 10.1262/jrd.2014-037] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Paired-related transcription factors, PRRX1 and PRRX2, which are present in mesenchymal tissues and participate in mesenchymal
cell differentiation, were recently found in the stem/progenitor cells of the pituitary gland of ectodermal origin. To clarify the
role of PRRX1 and PRRX2 in the pituitary gland, the present study first aimed to identify transcription factors that regulate
Prrx1 and Prrx2 expression. A promoter assay for the upstream regions of both genes was
performed by co-transfection of the expression vector of several transcription factors, many of which are frequently found in the
pituitary stem/progenitor cells. The results for the promoter activity of both genes showed expression in a cell type-dependent
manner. Comprehensive comparison of transcriptional activity of several transcription factors was performed with CHO cells, which
do not show Prrx1 and Prrx2 expression, and the results revealed the presence of common and
distinct factors for both genes. Among them, KLF6 showed specific and remarkable stimulation of Prrx2 expression.
In vitro experiments using an electrophoretic mobility shift assay and siRNA interference revealed a potential
ability for regulation of Prrx2 expression by KLF6. Finally, immunohistochemistry confirmed the presence of KLF6
in the SOX2/PRRX2 double-positive stem/progenitor cells of the postnatal pituitary gland. Thus, the finding of KLF6 might provide
a novel clue to clarify the maintenance of stem/progenitor cells of the postnatal pituitary gland.
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Affiliation(s)
- Hiroki Ueharu
- Laboratory of Molecular Biology and Gene Regulation, Division of Life Science, Graduate School of Agriculture, Meiji University, Kanagawa 214-8571, Japan
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Yoshida S, Higuchi M, Ueharu H, Nishimura N, Tsuda M, Yako H, Chen M, Mitsuishi H, Sano Y, Kato T, Kato Y. Characterization of murine pituitary-derived cell lines Tpit/F1, Tpit/E and TtT/GF. J Reprod Dev 2014; 60:295-303. [PMID: 24881870 PMCID: PMC4139504 DOI: 10.1262/jrd.2014-031] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The pituitary is an important endocrine tissue of the vertebrate that produces and secretes many hormones. Accumulating data
suggest that several types of cells compose the pituitary, and there is growing interest in elucidating the origin of these cell
types and their roles in pituitary organogenesis. Therein, the histogenous cell line is an extremely valuable experimental tool
for investigating the function of derived tissue. In this study, we compared gene expression profiles by microarray analysis and
real-time PCR for murine pituitary tumor-derived non-hormone-producing cell lines TtT/GF, Tpit/F1 and Tpit/E. Several genes are
characteristically expressed in each cell line: Abcg2, Nestin, Prrx1,
Prrx2, CD34, Eng, Cspg4 (Ng2),
S100β and nNos in TtT/GF; Cxcl12, Raldh1,
Msx1 and Twist1 in Tpit/F1; and Cxadr, Sox9,
Cdh1, EpCAM and Krt8 in Tpit/E. Ultimately, we came to the following conclusions: TtT/GF cells
show the most differentiated state, and may have some properties of the pituitary vascular endothelial cell and/or pericyte.
Tpit/F1 cells show the epithelial and mesenchymal phenotypes with stemness still in a transiting state. Tpit/E cells have a
phenotype of epithelial cells and are the most immature cells in the progression of differentiation or in the initial
endothelial-mesenchymal transition (EMT). Thus, these three cell lines must be useful model cell lines for investigating pituitary
stem/progenitor cells as well as organogenesis.
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Affiliation(s)
- Saishu Yoshida
- Laboratory of Molecular Biology and Gene Regulation, Division of Life Science, Graduate School of Agriculture, Meiji University, Kawasaki 214-8571, Japan
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Higuchi M, Kanno N, Yoshida S, Ueharu H, Chen M, Yako H, Shibuya S, Sekita M, Tsuda M, Mitsuishi H, Nishimura N, Kato T, Kato Y. GFP-expressing S100β-positive cells of the rat anterior pituitary differentiate into hormone-producing cells. Cell Tissue Res 2014; 357:767-79. [DOI: 10.1007/s00441-014-1890-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 04/08/2014] [Indexed: 01/04/2023]
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18
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PRRX1 and PRRX2 distinctively participate in pituitary organogenesis and a cell-supply system. Cell Tissue Res 2014; 357:323-35. [DOI: 10.1007/s00441-014-1861-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 02/20/2014] [Indexed: 12/15/2022]
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Chen M, Kato T, Higuchi M, Yoshida S, Yako H, Kanno N, Kato Y. Coxsackievirus and adenovirus receptor-positive cells compose the putative stem/progenitor cell niches in the marginal cell layer and parenchyma of the rat anterior pituitary. Cell Tissue Res 2013; 354:823-36. [DOI: 10.1007/s00441-013-1713-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 07/16/2013] [Indexed: 01/04/2023]
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Pérez-Millán MI, Zeidler MG, Saunders TL, Camper SA, Davis SW. Efficient, specific, developmentally appropriate cre-mediated recombination in anterior pituitary gonadotropes and thyrotropes. Genesis 2013; 51:785-92. [PMID: 23996951 DOI: 10.1002/dvg.22425] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 07/30/2013] [Accepted: 08/05/2013] [Indexed: 11/06/2022]
Abstract
Tissue-specific expression of cre recombinase is a well-established genetic tool to analyze gene function, and it is limited only by the efficiency and specificity of available cre mouse strains. Here, we report the generation of a transgenic line containing a cre cassette with codon usage optimized for mammalian cells (iCre) under the control of a mouse glycoprotein hormone α-subunit (αGSU) regulatory sequences in a bacterial artificial chromosome genomic clone. Initial analysis of this transgenic line, Tg(αGSU-iCre), with cre reporter strains reveals onset of cre activity in the differentiating cells of the developing anterior pituitary gland at embryonic day 12.5, with a pattern characteristic of endogenous αGSU. In adult mice, αGSU-iCre was active in the anterior lobe of the pituitary gland and in the cells that produce αGSU (gonadotropes and thyrotropes) with high penetrance. Little or no activity was observed in other tissues, including skeletal and cardiac muscle, brain, kidney, lungs, testis, ovary, and liver. This αGSU-iCre line is suitable for efficient, specific, and developmentally regulated deletion of floxed alleles in anterior pituitary gonadotropes and thyrotropes.
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Brannick KE, Craig ZR, Himes AD, Peretz JR, Wang W, Flaws JA, Raetzman LT. Prenatal exposure to low doses of bisphenol A increases pituitary proliferation and gonadotroph number in female mice offspring at birth. Biol Reprod 2012; 87:82. [PMID: 22875908 PMCID: PMC3507543 DOI: 10.1095/biolreprod.112.100636] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 05/09/2012] [Accepted: 08/01/2012] [Indexed: 12/15/2022] Open
Abstract
The pituitary gland is composed of hormone-producing cells essential for homeostasis and reproduction. Pituitary cells are sensitive to endocrine feedback in the adult and can have altered hormonal secretion from exposure to the endocrine disruptor bisphenol A (BPA). BPA is a prevalent plasticizer used in food and beverage containers, leading to widespread human exposure. Although prenatal exposure to BPA can impact reproductive function in the adult, the effects of BPA on the developing pituitary are unknown. We hypothesized that prenatal exposure to low doses of BPA impacts gonadotroph cell number or parameters of hormone synthesis. To test this, pregnant mice were administered 0.5 μg/kg/day of BPA, 50 μg/kg/day of BPA, or vehicle beginning on Embryonic Day 10.5. At parturition, pituitaries from female offspring exposed in utero to either dose of BPA had increased proliferation, as assessed by mKi67 mRNA levels and immunohistochemistry. Coincidently, gonadotroph number also increased in treated females. However, we observed a dichotomy between mRNA levels of Lhb and Fshb. Female mice exposed to 0.5 μg/kg/day BPA had increased mRNA levels of gonadotropins and the gonadotropin-receptor hormone (GNRH) receptor (Gnrhr), which mediates GNRH regulation of gonadotropin production and release. In contrast, mice treated with 50 μg/kg/day of BPA had decreased gonadotropin mRNA levels, Gnrhr and Nr5a1, a transcription factor required for gonadotroph differentiation. No other pituitary hormones were altered on the day of birth in response to in utero BPA exposure, and male pituitaries showed no change in the parameters tested. Collectively, these results show that prenatal exposure to BPA affects pituitary gonadotroph development in females.
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Affiliation(s)
- Katherine E. Brannick
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Zelieann R. Craig
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Ashley D. Himes
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Jackye R. Peretz
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Wei Wang
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Jodi A. Flaws
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Lori T. Raetzman
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois
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Tadjuidje E, Hegde RS. The Eyes Absent proteins in development and disease. Cell Mol Life Sci 2012; 70:1897-913. [PMID: 22971774 DOI: 10.1007/s00018-012-1144-9] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 07/24/2012] [Accepted: 08/20/2012] [Indexed: 10/27/2022]
Abstract
The Eyes Absent (EYA) proteins, first described in the context of fly eye development, are now implicated in processes as disparate as organ development, innate immunity, DNA damage repair, photoperiodism, angiogenesis, and cancer metastasis. These functions are associated with an unusual combination of biochemical activities: tyrosine phosphatase and threonine phosphatase activities in separate domains, and transactivation potential when associated with a DNA-binding partner. EYA mutations are linked to multiorgan developmental disorders, as well as to adult diseases ranging from dilated cardiomyopathy to late-onset sensorineural hearing loss. With the growing understanding of EYA biochemical and cellular activity, biological function, and association with disease, comes the possibility that the EYA proteins are amenable to the design of targeted therapeutics. The availability of structural information, direct links to disease states, available animal models, and the fact that they utilize unconventional reaction mechanisms that could allow specificity, suggest that EYAs are well-positioned for drug discovery efforts. This review provides a summary of EYA structure, activity, and function, as they relate to development and disease, with particular emphasis on recent findings.
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Affiliation(s)
- Emmanuel Tadjuidje
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
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Huai YT, Lan XY, Ma L, Wang J, Lei CZ, Chen H, Wang JQ. Novel mutation in TGA stop-codon of bovine SIX6 gene. Mol Biol 2011. [DOI: 10.1134/s0026893310061093] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Abstract
The pituitary gland represents the endocrine core of the body, and its hormonal output governs many key physiological processes. Because endocrine demands frequently change, the pituitary has to flexibly remodel its hormone-producing cell compartment. One mechanism of pituitary plasticity may rely on the generation of new hormonal cells from resident stem/progenitor cells. Existence of such 'master' cells in the pituitary has in the past repeatedly been postulated. Only recently, however, very plausible candidates have been identified that express stem cell-associated markers and signalling factors, and display the stem/progenitor cell characteristics of multipotency, efflux capacity (side population phenotype) and niche-like organization. In other adult tissues, stem cells recapitulate the embryonic developmental path on their course towards mature specialized cells. Interestingly, the pituitary stem/progenitor cell compartment shows prominent expression of transcriptional regulators and signalling factors that play a pivotal role during pituitary embryogenesis. This review summarizes the recent progress in pituitary stem/progenitor cell identification, highlights their potential embryonic phenotype, sketches a tentative stem/progenitor cell model, and discusses further research and challenges. Recognizing and scrutinizing the pituitary stem/progenitor cells as embryonic players in the adult gland may profoundly impact on our still poor understanding of the mechanisms underlying pituitary cell turnover and plasticity.
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Affiliation(s)
- Hugo Vankelecom
- Laboratory of Tissue Plasticity, Department of Molecular Cell Biology, University of Leuven (K.U.Leuven), B-3000 Leuven, Belgium.
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Proszkowiec-Weglarz M, Higgins SE, Porter TE. Changes in gene expression during pituitary morphogenesis and organogenesis in the chick embryo. Endocrinology 2011; 152:989-1000. [PMID: 21239434 DOI: 10.1210/en.2010-1021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The anterior pituitary gland plays an important role in the regulation of many physiological processes. Formation of Rathke's pouch (RP), the precursor of the anterior pituitary, involves evagination of the oral ectoderm in a multi-step process regulated by cell interactions, signaling pathways, and transcription factors. Chickens are an excellent model to study development because of the availability of large sample sizes, accurate timing of development, and embryo accessibility. The aim of this study was to quantify mRNA expression patterns in the developing chicken anterior pituitary to evaluate the chicken embryo as a model for mammalian pituitary development. The expression profiles of 16 genes differentially expressed in RP and neuroectoderm were determined in this study. Among these, Pitx1, Pitx2, and Hesx1 mRNA levels were high on embryonic days (e) 2.5 to e3 in RP and decreased during development. Expression of Pit1 and Tbx19 mRNA in RP reached the highest levels by e7 and e6.5, respectively. Levels of glycoprotein subunit α mRNA increased beginning at e4. FGF8 mRNA showed the highest expression at e3 to e3.5 in neuroectoderm. BMP2 showed slight decreases in mRNA expression in both tissues during development, while Isl1 and Noggin mRNA expression increased in later development. Taken together, we present the first quantitative transcriptional profile of pituitary organogenesis. Our results will help further understanding of the functional development of this gland. Moreover, because of the high similarity in gene expression patterns observed between chicken and mouse, chickens could serve as an excellent model to study genetic and molecular mechanisms underlying pituitary development.
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Abstract
Gene regulatory networks (GRNs) provide system level explanations of developmental and physiological functions in the terms of the genomic regulatory code. Depending on their developmental functions, GRNs differ in their degree of hierarchy, and also in the types of modular sub-circuit of which they are composed, although there is a commonly employed sub-circuit repertoire. Mathematical modelling of some types of GRN sub-circuit has deepened biological understanding of the functions they mediate. The structural organization of various kinds of GRN reflects their roles in the life process, and causally illuminates both developmental and evolutionary process.
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Affiliation(s)
- Eric H Davidson
- Division of Biology 156-29, California Institute of Technology, Pasadena, California 91125, USA.
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Monahan P, Rybak S, Raetzman LT. The notch target gene HES1 regulates cell cycle inhibitor expression in the developing pituitary. Endocrinology 2009; 150:4386-94. [PMID: 19541765 PMCID: PMC2736073 DOI: 10.1210/en.2009-0206] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The pituitary is an endocrine gland responsible for the release of hormones, which regulate growth, metabolism, and reproduction. Diseases such as hypopituitarism or pituitary adenomas are able to disrupt pituitary function leading to suboptimal function of the entire endocrine system. Growth of the pituitary during development and adulthood is a tightly regulated process. Hairy and enhancer of split (HES1), a transcription factor whose expression is initiated by the Notch signaling pathway, is a repressor of cell cycle inhibitors. We hypothesize that with the loss of Hes1, pituitary progenitors are no longer maintained in a proliferative state, choosing instead to exit the cell cycle. To test this hypothesis, we examined the expression of cell cycle regulators in wild-type and Hes1-deficient pituitaries. Our studies indicate that in early pituitary development [embryonic day (e) 10.5], cells contained in the Rathke's pouch of Hes1 mutants have decreased proliferation, indicated by changes in phosphohistone H3 expression. Furthermore, pituitaries lacking Hes1 have increased cell cycle exit, shown by significant increases in the cyclin-dependent kinase inhibitors, p27 and p57, from e10.5 to e14.5. Additionally, Hes1 mutant pituitaries have ectopic expression of p21 in Rathke's pouch progenitors, an area coincident with increased cell death. These observations taken together indicate a role for HES1 in the control of cell cycle exit and in mediating the balance between proliferation and differentiation, allowing for the properly timed emergence of hormone secreting cell types.
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Affiliation(s)
- Pamela Monahan
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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Kotsampasi B, Chadio S, Papadomichelakis G, Deligeorgis S, Kalogiannis D, Menegatos I, Zervas G. Effects of Maternal Undernutrition on the Hypothalamic-Pituitary-Gonadal Axis Function in Female Sheep Offspring. Reprod Domest Anim 2009; 44:677-84. [DOI: 10.1111/j.1439-0531.2007.01046.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Abstract
Background: Cancerous stem-like cells (CSCs) have been implicated as cancer-initiating cells in a range of malignant tumours. Diverse genetic programs regulate CSC behaviours, and CSCs from glioblastoma patients are qualitatively distinct from each other. The intrinsic connection between the presence of CSCs and malignancy is unclear. We set out to test whether tumour stem-like cells can be identified from benign tumours. Methods: Tumour sphere cultures were derived from hormone-positive and -negative pituitary adenomas. Characterisation of tumour stem-like cells in vitro was performed using self-renewal assays, stem cell-associated marker expression analysis, differentiation, and stimulated hormone production assays. The tumour-initiating capability of these tumour stem-like cells was tested in serial brain tumour transplantation experiments using SCID mice. Results: In this study, we isolated sphere-forming, self-renewable, and multipotent stem-like cells from pituitary adenomas, which are benign tumours. We found that pituitary adenoma stem-like cells (PASCs), compared with their differentiated daughter cells, expressed increased levels of stem cell-associated gene products, antiapoptotic proteins, and pituitary progenitor cell markers. Similar to CSCs isolated from glioblastomas, PASCs are more resistant to chemotherapeutics than their differentiated daughter cells. Furthermore, differentiated PASCs responded to stimulation with hypothalamic hormones and produced corresponding pituitary hormones that are reflective of the phenotypes of the primary pituitary tumours. Finally, we demonstrated that PASCs are pituitary tumour-initiating cells in serial transplantation animal experiments. Conclusion: This study for the first time indicates that stem-like cells are present in benign tumours. The conclusions from this study may have applications to understanding pituitary tumour biology and therapies, as well as implications for the notion of tumour-initiating cells in general.
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Gaston-Massuet C, Andoniadou CL, Signore M, Sajedi E, Bird S, Turner JM, Martinez-Barbera JP. Genetic interaction between the homeobox transcription factors HESX1 and SIX3 is required for normal pituitary development. Dev Biol 2008; 324:322-33. [PMID: 18775421 PMCID: PMC3606136 DOI: 10.1016/j.ydbio.2008.08.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 08/06/2008] [Accepted: 08/08/2008] [Indexed: 10/21/2022]
Abstract
Hesx1 has been shown to be essential for normal pituitary development. The homeobox gene Six3 is expressed in the developing pituitary gland during mouse development but its function in this tissue has been precluded by the fact that in the Six3-deficient embryos the pituitary gland is not induced. To gain insights into the function of Six3 during pituitary development we have generated Six3+/- ;Hesx1Cre/+ double heterozygous mice. Strikingly, these mice show marked dwarfism, which is first detectable around weaning, and die by the 5th-6th week of age. Thyroid and gonad development is also impaired in these animals. Analysis of Six3+/- ;Hesx1Cre/+ compound embryos indicates that hypopituitarism is the likely cause of these defects since pituitary development is severely impaired in these mutants. Similar to the Hesx1-deficient embryos, Rathke's pouch is initially expanded in Six3+/- ;Hesx1Cre/+ compound embryos due to an increase in cell proliferation. Subsequently, the anterior pituitary gland appears bifurcated, dysmorphic and occasionally ectopically misplaced in the nasopharyngeal cavity, but cell differentiation is unaffected. Our research has revealed a role for Six3 in normal pituitary development, which has likely been conserved during evolution as SIX3 is also expressed in the pituitary gland of the human embryo.
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Affiliation(s)
- Carles Gaston-Massuet
- Neural Development Unit, Institute of Child Health, University College London, London, UK
| | - Cynthia L. Andoniadou
- Neural Development Unit, Institute of Child Health, University College London, London, UK
| | - Massimo Signore
- Neural Development Unit, Institute of Child Health, University College London, London, UK
| | - Ezat Sajedi
- Neural Development Unit, Institute of Child Health, University College London, London, UK
| | - Sophie Bird
- Neural Development Unit, Institute of Child Health, University College London, London, UK
| | - James M.A. Turner
- Developmental Genetics and Stem Cell Research, National Institute for Medical Research, Mill Hill, London
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Rajendran RS, Wellbrock UM, Zupanc GKH. Apoptotic cell death, long-term persistence, and neuronal differentiation of aneuploid cells generated in the adult brain of teleost fish. Dev Neurobiol 2008; 68:1257-68. [PMID: 18563701 DOI: 10.1002/dneu.20656] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Aneuploidy, caused by segregation defects during mitosis, has previously been identified in adult-born cells of mammals and teleosts. In the present study, we have examined the fate of these cells in the brain of the teleost fish Apteronotus leptorhynchus. By immunostaining against active caspase-3, we have shown that both cells with normal nuclear morphology and cells with mitotic segregation defects undergo apoptosis, but the relative number of apoptotic cells is higher among cells of the latter category. Long-term survival of cells with mitotic segregation defects could be demonstrated by incorporation of 5-bromo-2'-deoxyuridine into newly synthesized DNA during the S-phase of mitosis, and by employment of postadministration survival times of up to 860 days. Moreover, by combining 5-bromo-2'-deoxyuridine immunolabeling with immunostaining against the neuron-specific marker protein Hu, we have shown that among the long-term persistent cells with mitotic segregation defects a similar portion develops into neurons as does among the long-term persistent cells without such defects. It is possible that aneuploid cells play a role in the regulation of gene expression by somatic genomic alterations during postnatal development.
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Affiliation(s)
- R Samuel Rajendran
- School of Engineering and Science, Jacobs University Bremen, 28725 Bremen, Germany
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Vieira TC, Boldarine VT, Abucham J. Molecular analysis of PROP1, PIT1, HESX1, LHX3, and LHX4 shows high frequency of PROP1 mutations in patients with familial forms of combined pituitary hormone deficiency. ACTA ACUST UNITED AC 2008; 51:1097-103. [PMID: 18157385 DOI: 10.1590/s0004-27302007000700012] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2006] [Accepted: 03/20/2007] [Indexed: 11/22/2022]
Abstract
UNLABELLED Combined Pituitary Hormone Deficiency (CPHD) is a prevalent disease in Neuroendocrinology services. The genetic form of CPHD may originate from mutations in pituitary transcription factor (PTF) genes and the pituitary image in these cases may give a clue of what PTF is most probably mutated: defects in LHX4 are usually associated with ectopic posterior pituitary (EPP); defects in LHX3, PIT1, and PROP1, with normally placed posterior pituitary (NPPP); HESX1 mutations are associated with both. OBJECTIVE To identify mutations in PTF genes in patients with idiopathic hypopituitarism followed in our service, based on the presence or absence of EPP on sellar MRI. METHODS Forty patients with idiopathic hypopituitarism (36 families, 9 consanguineous), followed in the Neuroendocrinology Outpatient Clinic of UNIFESP, Brazil, were submitted to sequencing analyses of PTF genes as follows: LHX3, HESX1, PIT1, and PROP1 were sequenced in patients with NPPP (26/40) and HESX1 and LHX4 in patients with EPP (14/40). RESULTS We identified only PROP1 mutations in 9 out of 26 patients with CPHD and NPPP (35%). Since eight of them came from 4 consanguineous families, the prevalence of PROP1 mutations was higher when only consanguineous families were considered (44%, 4/9). At the end of the study, we decided to sequence PROP1 in patients with EPP, just to confirm that they were not candidates for PROP1 mutations. No patients with EPP had PROP1 or other PTF mutations. CONCLUSIONS Patients with idiopathic CPHD and NPPP, born from consanguineous parents, are the strong candidates for PROP1 mutations. Other developmental gene(s) may be involved in the genesis of idiopathic hypopituitarism associated with EPP.
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Affiliation(s)
- Teresa C Vieira
- Division of Endocrinology, Department of Medicine, Universidade Federal de São Paulo, São Paulo, SP
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Grigoryan T, Wend P, Klaus A, Birchmeier W. Deciphering the function of canonical Wnt signals in development and disease: conditional loss- and gain-of-function mutations of beta-catenin in mice. Genes Dev 2008; 22:2308-41. [PMID: 18765787 PMCID: PMC2749675 DOI: 10.1101/gad.1686208] [Citation(s) in RCA: 453] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Wnt signaling is one of a handful of powerful signaling pathways that play crucial roles in the animal life by controlling the genetic programs of embryonic development and adult homeostasis. When disrupted, these signaling pathways cause developmental defects, or diseases, among them cancer. The gateway of the canonical Wnt pathway, which contains >100 genes, is an essential molecule called beta-catenin (Armadillo in Drosophila). Conditional loss- and gain-of-function mutations of beta-catenin in mice provided powerful tools for the functional analysis of canonical Wnt signaling in many tissues and organs. Such studies revealed roles of Wnt signaling that were previously not accessible to genetic analysis due to the early embryonic lethality of conventional beta-catenin knockout mice, as well as the redundancy of Wnt ligands, receptors, and transcription factors. Analysis of conditional beta-catenin loss- and gain-of-function mutant mice demonstrated that canonical Wnt signals control progenitor cell expansion and lineage decisions both in the early embryo and in many organs. Canonical Wnt signaling also plays important roles in the maintenance of various embryonic or adult stem cells, and as recent findings demonstrated, in cancer stem cell types. This has opened new opportunities to model numerous human diseases, which have been associated with deregulated Wnt signaling. Our review summarizes what has been learned from genetic studies of the Wnt pathway by the analysis of conditional beta-catenin loss- and gain-of-function mice.
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Affiliation(s)
- Tamara Grigoryan
- Max-Delbück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Peter Wend
- Max-Delbück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Alexandra Klaus
- Max-Delbück Center for Molecular Medicine, 13125 Berlin, Germany
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Shima Y, Zubair M, Komatsu T, Oka S, Yokoyama C, Tachibana T, Hjalt TA, Drouin J, Morohashi KI. Pituitary homeobox 2 regulates adrenal4 binding protein/steroidogenic factor-1 gene transcription in the pituitary gonadotrope through interaction with the intronic enhancer. Mol Endocrinol 2008; 22:1633-46. [PMID: 18417734 PMCID: PMC5419436 DOI: 10.1210/me.2007-0444] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2007] [Accepted: 04/08/2008] [Indexed: 11/19/2022] Open
Abstract
Ad4BP/SF-1 [adrenal4 binding protein/steroidogenic factor-1 (NR5A1)] is a factor important for animal reproduction and endocrine regulation, and its expression is tightly regulated in the gonad, adrenal gland, ventromedial hypothalamic nucleus, and pituitary gonadotrope. Despite its functional significance in the pituitary, the mechanisms underlying pituitary-specific expression of the gene remain to be uncovered. In this study, we demonstrate by transgenic mouse assays that the pituitary gonadotrope-specific enhancer is localized within the sixth intron of the gene. Functionally, the enhancer recapitulates endogenous Ad4BP/SF-1 expression in the fetal Rathke's pouch to the adult pituitary gonadotrope. Structurally, the enhancer consists of several elements conserved among animal species. Mutational analyses confirmed the significance of these elements for the enhancer function. One of these elements was able to interact both in vitro and in vivo with Pitx2 (pituitary homeobox 2), demonstrating that pituitary homeobox 2 regulates Ad4BP/SF-1 gene transcription in the pituitary gonadotrope via interaction with the gonadotrope-specific enhancer.
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Affiliation(s)
- Yuichi Shima
- Division for Sex Differentiation, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Japan
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35
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Ishimaru Y, Komatsu T, Kasahara M, Katoh-Fukui Y, Ogawa H, Toyama Y, Maekawa M, Toshimori K, Chandraratna RAS, Morohashi KI, Yoshioka H. Mechanism of asymmetric ovarian development in chick embryos. Development 2008; 135:677-85. [PMID: 18199582 DOI: 10.1242/dev.012856] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
In most animals, the gonads develop symmetrically, but most birds develop only a left ovary. A possible role for estrogen in this asymmetric ovarian development has been proposed in the chick, but the mechanism underlying this process is largely unknown. Here, we identify the molecular mechanism responsible for this ovarian asymmetry. Asymmetric PITX2 expression in the left presumptive gonad leads to the asymmetric expression of the retinoic-acid (RA)-synthesizing enzyme, RALDH2, in the right presumptive gonad. Subsequently, RA suppresses expression of the nuclear receptors Ad4BP/SF-1 and estrogen receptor alpha in the right ovarian primordium. Ad4BP/SF-1 expressed in the left ovarian primordium asymmetrically upregulates cyclin D1 to stimulate cell proliferation. These data suggest that early asymmetric expression of PITX2 leads to asymmetric ovarian development through up- or downregulation of RALDH2, Ad4BP/SF-1, estrogen receptor alpha and cyclin D1.
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Affiliation(s)
- Yoshiyasu Ishimaru
- Department of Natural Sciences, Hyogo University of Teacher Education, 942-1, Shimokume, Kato, Hyogo 673-1494, Japan
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36
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Abstract
The pituitary gland is a critical endocrine organ that controls homeostasis, metabolism, reproduction and growth. Pituitary organogenesis involves the initial proliferation process of progenitor cells and the subsequent differentiation process into distinct cell types. Although various signaling molecules and transcription factors play roles in the pituitary development, the mechanisms that control progenitor cells remain to be elucidated. The mammalian Hes basic helix-loop-helix genes, known as Notch effectors, play essential roles in the development of various tissues and organs by maintaining progenitor cells in an undifferentiated state and by regulating binary cell fate decisions. Recently, it has been reported that Hes genes play crucial roles in pituitary development by regulating progenitor cells. This review describes essential roles of Hes genes in pituitary development.
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Affiliation(s)
- Masato Hojo
- a Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Aya Kita
- b Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan and Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Ryoichiro Kageyama
- c Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Nobuo Hashimoto
- d Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
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37
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Zhu X, Gleiberman AS, Rosenfeld MG. Molecular physiology of pituitary development: signaling and transcriptional networks. Physiol Rev 2007; 87:933-63. [PMID: 17615393 DOI: 10.1152/physrev.00006.2006] [Citation(s) in RCA: 237] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The pituitary gland is a central endocrine organ regulating basic physiological functions, including growth, the stress response, reproduction, metabolic homeostasis, and lactation. Distinct hormone-producing cell types in the anterior pituitary arise from a common ectodermal primordium during development by extrinsic and intrinsic mechanisms, providing a powerful model system for elucidating general principles in mammalian organogenesis. The central purpose of this review is to inspect the integrated signaling and transcriptional events that affect precursor proliferation, cell lineage commitment, terminal differentiation, and physiological regulation by hypothalamic tropic factors.
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Affiliation(s)
- Xiaoyan Zhu
- Howard Hughes Medical Institute, Department and School of Medicine, University of California, San Diego, La Jolla, California 92093, USA.
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38
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Veitia RA, Salazar-Ciudad I. Commonalities in fly embryogenesis and mammalian pituitary patterning. Trends Endocrinol Metab 2007; 18:261-5. [PMID: 17693094 DOI: 10.1016/j.tem.2007.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Revised: 06/13/2007] [Accepted: 08/03/2007] [Indexed: 11/13/2022]
Abstract
During embryonic development, morphogenetic gradients can specify the formation of gene expression territories. Here, we explore possible commonalities between pattern formation in the Drosophila blastoderm and murine pituitary. Shared principles include the need for positive feedback involving fate-determining genes to maintain a differentiated state, and the existence of intra- or extracellular inhibitory signals that improve spatial resolution of neighboring territories. The precision of spatial segregation is, however, limited by stochastic gene expression. Variability in gene expression at territory boundaries might give rise to a poorly differentiated pool of cells, which could harbor stem-like properties. The ideas outlined here deserve further theoretical and experimental exploration.
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Affiliation(s)
- Reiner A Veitia
- Institut Cochin, Université Paris Descartes, CNRS (UMR 8104), Paris, France.
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39
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Savage JJ, Mullen RD, Sloop KW, Colvin SC, Camper SA, Franklin CL, Rhodes SJ. Transgenic mice expressing LHX3 transcription factor isoforms in the pituitary: effects on the gonadotrope axis and sex-specific reproductive disease. J Cell Physiol 2007; 212:105-17. [PMID: 17311285 DOI: 10.1002/jcp.21010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The LHX3 transcription factor plays critical roles in pituitary and nervous system development. Mutations in the human LHX3 gene cause severe hormone deficiency diseases. The gene produces two mRNAs which can be translated to three protein isoforms. The LHX3a protein contains a central region with LIM domains and a homeodomain, and a carboxyl terminus with the major transactivation domain. LHX3b is identical to LHX3a except that it has a different amino terminus. M2-LHX3 lacks the amino terminus and LIM domains of LHX3a/b. In vitro experiments have demonstrated these three proteins have different biochemical and gene regulatory properties. Here, to investigate the effects of overexpression of LHX3 in vivo, the alpha glycoprotein subunit (alphaGSU) promoter was used to produce LHX3a, LHX3b, and M2-LHX3 in the pituitary glands of transgenic mice. Alpha GSU-beta galactosidase animals were generated as controls. Male alphaGSU-LHX3a and alphaGSU-LHX3b mice are infertile and die at a young age as a result of complications associated with obstructive uropathy including uremia. These animals have a reduced number of pituitary gonadotrope cells, low circulating gonadotropins, and possible sex hormone imbalance. Female alphaGSU-LHX3a and alphaGSU-LHX3b transgenic mice are viable but have reduced fertility. By contrast, alphaGSU-M2-LHX3 mice and control mice expressing beta galactosidase are reproductively unaffected. These overexpression studies provide insights into the properties of LHX3 during pituitary development and highlight the importance of this factor in reproductive physiology.
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Affiliation(s)
- Jesse J Savage
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
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40
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Pogoda HM, Hammerschmidt M. Molecular genetics of pituitary development in zebrafish. Semin Cell Dev Biol 2007; 18:543-58. [PMID: 17560816 DOI: 10.1016/j.semcdb.2007.04.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Accepted: 04/10/2007] [Indexed: 11/21/2022]
Abstract
The pituitary gland of vertebrates consists of two major parts, the neurohypophysis (NH) and the adenohypophysis (AH). As a central part of the hypothalamo-hypophyseal system (HHS), it constitutes a functional link between the nervous and the endocrine system to regulate basic body functions, such as growth, metabolism and reproduction. The development of the AH has been intensively studied in mouse, serving as a model for organogenesis and differential cell specification. However, given that the AH is a relatively recent evolutionary advance of the chordate phylum, it is also interesting to understand its development in lower chordate systems. In recent years, the zebrafish has emerged as a powerful lower vertebrate system for developmental studies, being amenable for large-scale genetic approaches, embryological manipulations, and in vivo imaging. Here, we present an overview of current knowledge of the mechanisms and genetic control of pituitary formation during zebrafish development. First, we describe the components of the zebrafish HHS, and the different pituitary cell types and hormones, followed by a description of the different steps of normal pituitary development. The central part of the review deals with the genes found to be essential for zebrafish AH development, accompanied by a description of the corresponding mutant phenotypes. Finally, we discuss future directions, with particular focus on evolutionary aspects, and some novel functional aspects with growing medical and social relevance.
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Affiliation(s)
- Hans-Martin Pogoda
- Max-Planck Institute of Immunobiology, Stübeweg 51, D-79108 Freiburg, Germany
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41
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Kita A, Imayoshi I, Hojo M, Kitagawa M, Kokubu H, Ohsawa R, Ohtsuka T, Kageyama R, Hashimoto N. Hes1 and Hes5 control the progenitor pool, intermediate lobe specification, and posterior lobe formation in the pituitary development. Mol Endocrinol 2007; 21:1458-66. [PMID: 17426285 DOI: 10.1210/me.2007-0039] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The pituitary gland is composed of two distinct entities: the adenohypophysis, including the anterior and intermediate lobes, and the neurohypophysis, known as the posterior lobe. This critical endocrine organ is essential for homeostasis, metabolism, reproduction, and growth. The pituitary development requires the control of proliferation and differentiation of progenitor cells. Although multiple signaling molecules and transcription factors are required for the proper pituitary development, the mechanisms that regulate the fate of progenitor cells remain to be elucidated. Hes genes, known as Notch effectors, play a crucial role in specifying cellular fates during the development of various tissues and organs. Here, we report that mice deficient for Hes1 and Hes5 display severe pituitary hypoplasia caused by accelerated differentiation of progenitor cells. In addition, this hypoplastic pituitary gland (adenohypophysis) lacks the intermediate lobe and exhibits the features of the anterior lobe only. Hes1 and Hes5 double-mutant mice also lack the neurohypophysis (the posterior lobe), probably due to incomplete evagination of the diencephalon. Thus, Hes genes control not only maintenance of progenitor cells but also intermediate vs. anterior lobe specification during the adenohypophysis development. Hes genes are also essential for the formation of the neurohypophysis.
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Affiliation(s)
- Aya Kita
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
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42
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Kozmik Z, Holland ND, Kreslova J, Oliveri D, Schubert M, Jonasova K, Holland LZ, Pestarino M, Benes V, Candiani S. Pax-Six-Eya-Dach network during amphioxus development: conservation in vitro but context specificity in vivo. Dev Biol 2007; 306:143-59. [PMID: 17477914 DOI: 10.1016/j.ydbio.2007.03.009] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2007] [Revised: 02/18/2007] [Accepted: 03/07/2007] [Indexed: 12/23/2022]
Abstract
The Drosophila retinal determination gene network occurs in animals generally as a Pax-Six-Eyes absent-Dachshund network (PSEDN). For amphioxus, we describe the complete network of nine PSEDN genes, four of which-AmphiSix1/2, AmphiSix4/5, AmphSix3/6, and AmphiEya-are characterized here for the first time. For amphioxus, in vitro interactions among the genes and proteins of the network resemble those of other animals, except for the absence of Dach-Eya binding. Amphioxus PSEDN genes are expressed in highly stage- and tissue-specific patterns (sometimes conspicuously correlated with the local intensity of cell proliferation) in the gastrular organizer, notochord, somites, anterior central nervous system, peripheral nervous system, pharyngeal endoderm, and the likely homolog of the vertebrate adenohypophysis. In this last tissue, the anterior region expresses all three amphioxus Six genes and is a zone of active cell proliferation, while the posterior region expresses only AmphiPax6 and is non-proliferative. In summary, the topologies of animal PSEDNs, although considerably more variable than originally proposed, are conserved enough to be recognizable among species and among developing tissues; this conservation may reflect indispensable involvement of PSEDNs during the critically important early phases of embryology (e.g. in the control of mitosis, apoptosis, and cell/tissue motility).
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Affiliation(s)
- Zbynek Kozmik
- Institute of Molecular Genetics, Videnska 1083, 14220 Prague 4, Czech Republic
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43
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Rajendran RS, Zupanc MM, Lösche A, Westra J, Chun J, Zupanc GKH. Numerical chromosome variation and mitotic segregation defects in the adult brain of teleost fish. Dev Neurobiol 2007; 67:1334-47. [PMID: 17638379 DOI: 10.1002/dneu.20365] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Teleost fish are distinguished by their enormous potential for the generation of new cells in both the intact and the injured adult brain. Here, we present evidence that these cells are a genetic mosaic caused by somatic genomic alteration. Metaphase chromosome spreads from whole brains of the teleost Apteronotus leptorhynchus revealed an euploid complement of 22 chromosomes in only 22% of the cells examined. The rate of aneuploidy is substantially higher in brain cells than in liver cells, as shown by both metaphase chromosome spreads and flow cytometric analysis. Among the aneuploid cells in the brain, approximately 84% had fewer, and the remaining 16% more, than 22 chromosomes. Typically, multiple chromosomes were lost or gained. The aneuploidy is putatively caused by segregation defects during mitotic division. Labeling of condensed chromosomes of M-phase cells by phosphorylated histone-H3 revealed laggards, anaphase bridges, and micronuclei, all three of which indicate displaced mitotic chromosomes. Quantitative analysis has shown that in the entire brain on average 14% of all phosphorylated histone-H3-labeled cells exhibit such signs of segregation defects. Together with the recent discovery of aneuploidy in the adult mammalian brain, the results of the present investigation suggest that the loss or gain of chromosomes might provide a mechanism to regulate gene expression during development of new cells in the adult vertebrate brain.
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Affiliation(s)
- R Samuel Rajendran
- School of Engineering and Science, Jacobs University Bremen, D-28725 Bremen, Germany
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44
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Raetzman LT, Cai JX, Camper SA. Hes1 is required for pituitary growth and melanotrope specification. Dev Biol 2006; 304:455-66. [PMID: 17367776 PMCID: PMC1913046 DOI: 10.1016/j.ydbio.2006.11.010] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2006] [Revised: 10/25/2006] [Accepted: 11/06/2006] [Indexed: 11/23/2022]
Abstract
Rathke's pouch contains progenitor cells that differentiate into the endocrine cells of the pituitary gland. It gives rise to gonadotrope, thyrotrope, somatotrope, corticotrope and lactotrope cells in the anterior lobe and the intermediate lobe melanotropes. Pituitary precursor cells express many members of the Notch signaling pathway including the downstream effector gene Hes1. We hypothesized that Hes1 regulates the timing of precursor differentiation and cell fate determination. To test this idea, we expressed Hes1 in differentiating pituitary cells and found that it can inhibit gonadotrope and thyrotrope differentiation. Pituitaries of Hes1 deficient mice have anterior lobe hypoplasia. All cells in the anterior lobe are specified and differentiate, but an early period of increased cell death and reduced proliferation causes reduced growth, evident as early as e14.5. In addition, cells within the intermediate lobe differentiate into somatotropes instead of melanotropes. Thus, the Hes1 repressor is essential for melanotrope specification. These results demonstrate that Notch signaling plays multiple roles in pituitary development, influencing precursor number, organ size, cell differentiation and ultimately cell fate.
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45
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Pope C, McNeilly JR, Coutts S, Millar M, Anderson RA, McNeilly AS. Gonadotrope and thyrotrope development in the human and mouse anterior pituitary gland. Dev Biol 2006; 297:172-81. [PMID: 16806148 DOI: 10.1016/j.ydbio.2006.05.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2005] [Revised: 04/11/2006] [Accepted: 05/05/2006] [Indexed: 11/20/2022]
Abstract
Genes and orthologous intrinsic and extrinsic factors critical for embryonic pituitary gonadotrope and thyrotrope cell differentiation have been identified mainly in rodents, but data on the human are very limited. In human fetal pituitaries examined between 14 and 19 weeks of gestation using immunofluorescent confocal microscopy, we found that most fetal gonadotropes expressed alpha-GSU, LHbeta, and FSHbeta gonadotropin subunits while almost no cells expressed alpha-GSU and LHbeta alone. Gonadotropes expressing alpha-GSU and FSHbeta only were detected in both male and female pituitaries, increasing in proportion to total gonadotropes in both males and females from 14 (approximately 4.5%) to 19 weeks (approximately 16.5%) with a peak in males of 45.5% compared with females of 16.5% at 17 weeks of gestation. When FSHbeta or LHbeta genes were expressed, gonadotropes were non-dividing. This profile of human fetal gonadotrope development differs from the current mouse model. Furthermore, while expression of alpha-GSU appears to be the lead protein in gonadotropes, in thyrotropes which ultimately express alpha-GSU with TSHbeta, we observed that most if not all thyrotropes were TSHbeta-positive but alpha-GSU-negative until around 19 weeks in human, and e15 in mouse, fetal pituitaries. Furthermore, the TSHbeta-only thyrotropes were dividing, and TSHbeta rather than alpha-GSU was the lead protein in thyrotrope development. Thus, while biologically active dimeric FSH and LH can be produced by the human fetal pituitary by 14 weeks, dimeric biologically active TSH will only be produced from around 17 weeks of gestation. The mechanism(s) responsible for the different molecular regulation of alpha-GSU gene expression in gonadotropes and thyrotropes in the developing human fetal pituitary now requires investigation.
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Affiliation(s)
- Caroline Pope
- Medical Research Council Human Reproductive Sciences Unit, Centre for Reproductive Biology, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
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46
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Schlosser G. Induction and specification of cranial placodes. Dev Biol 2006; 294:303-51. [PMID: 16677629 DOI: 10.1016/j.ydbio.2006.03.009] [Citation(s) in RCA: 282] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2005] [Revised: 12/22/2005] [Accepted: 12/23/2005] [Indexed: 12/17/2022]
Abstract
Cranial placodes are specialized regions of the ectoderm, which give rise to various sensory ganglia and contribute to the pituitary gland and sensory organs of the vertebrate head. They include the adenohypophyseal, olfactory, lens, trigeminal, and profundal placodes, a series of epibranchial placodes, an otic placode, and a series of lateral line placodes. After a long period of neglect, recent years have seen a resurgence of interest in placode induction and specification. There is increasing evidence that all placodes despite their different developmental fates originate from a common panplacodal primordium around the neural plate. This common primordium is defined by the expression of transcription factors of the Six1/2, Six4/5, and Eya families, which later continue to be expressed in all placodes and appear to promote generic placodal properties such as proliferation, the capacity for morphogenetic movements, and neuronal differentiation. A large number of other transcription factors are expressed in subdomains of the panplacodal primordium and appear to contribute to the specification of particular subsets of placodes. This review first provides a brief overview of different cranial placodes and then synthesizes evidence for the common origin of all placodes from a panplacodal primordium. The role of various transcription factors for the development of the different placodes is addressed next, and it is discussed how individual placodes may be specified and compartmentalized within the panplacodal primordium. Finally, tissues and signals involved in placode induction are summarized with a special focus on induction of the panplacodal primordium itself (generic placode induction) and its relation to neural induction and neural crest induction. Integrating current data, new models of generic placode induction and of combinatorial placode specification are presented.
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Affiliation(s)
- Gerhard Schlosser
- Brain Research Institute, AG Roth, University of Bremen, FB2, 28334 Bremen, Germany.
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47
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Granger A, Bleux C, Kottler ML, Rhodes SJ, Counis R, Laverrière JN. The LIM-homeodomain proteins Isl-1 and Lhx3 act with steroidogenic factor 1 to enhance gonadotrope-specific activity of the gonadotropin-releasing hormone receptor gene promoter. Mol Endocrinol 2006; 20:2093-108. [PMID: 16613990 DOI: 10.1210/me.2005-0184] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The GnRH receptor (GnRH-R) plays a central role in mammalian reproductive function throughout adulthood. It also appears as an early marker gene of the presumptive gonadotrope lineage in developing pituitary. Here, using transient transfections combined with DNA/protein interaction assays, we have delineated cis-acting elements within the rat GnRH-R gene promoter that represent targets for the LIM-homeodomain (LIM-HD) proteins, Isl-1 and Lhx3. These factors, critical in early pituitary development, are thus also crucial for gonadotrope-specific expression of the GnRH-R gene. In heterologous cells, the expression of Isl-1 and Lhx3, together with steroidogenic factor 1 (SF-1), culminates in the activation of both the rat as well as human GnRH-R promoter, suggesting that this combination is evolutionarily conserved among mammals. The specificity of these LIM-HD factors is attested by the inefficiency of related proteins, including Lhx5 and Lhx9, to activate the GnRH-R gene promoter, as well as by the repressive capacity of a dominant-negative derivative of Lhx3. Accordingly, targeted deletion of the LIM response element decreases promoter activity. In addition, experiments with Gal4-SF-1 fusion proteins suggest that LIM-HD protein activity in gonadotrope cells is dependent upon SF-1 binding. Finally, using a transgenic model that allows monitoring of in vivo promoter activity, we show that the overlapping expression of Isl-1 and Lhx3 in the developing pituitary correlates with promoter activity. Collectively, these data suggest the occurrence of a specific LIM-HD pituitary code and designate the GnRH-R gene as the first identified transcriptional target of Isl-1 in the anterior pituitary.
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Affiliation(s)
- Anne Granger
- Physiologie de l'Axe Gonadotrope, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7079, Physiologie et Physiopathologie, Université Pierre et Marie Curie-Paris6, 4 place Jussieu, 75252 Paris cedex 05, France
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48
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Bhangoo APS, Hunter CS, Savage JJ, Anhalt H, Pavlakis S, Walvoord EC, Ten S, Rhodes SJ. Clinical case seminar: a novel LHX3 mutation presenting as combined pituitary hormonal deficiency. J Clin Endocrinol Metab 2006; 91:747-53. [PMID: 16394081 DOI: 10.1210/jc.2005-2360] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT LHX3 encodes LIM homeodomain class transcription factors with important roles in pituitary and nervous system development. The only previous report of LHX3 mutations described patients with two types of recessive mutations displaying combined pituitary hormone deficiency coupled with neck rigidity. OBJECTIVE We report a patient presenting a unique phenotype associated with a novel mutation in the LHX3 gene. PATIENT We report a 6-yr, 9-month-old boy born from a consanguineous relationship who presented shortly after birth with cyanosis, feeding difficulty, persistent jaundice, micropenis, and poor weight gain and growth rate. Laboratory data, including an undetectable TSH, low free T4, low IGF-I and IGF binding protein-3, prolactin deficiency, and LH and FSH deficiency were consistent with hypopituitarism. A rigid cervical spine leading to limited head rotation was noticed on follow-up examination. Magnetic resonance imaging revealed an apparently structurally normal cervical spine and a postcontrast hypointense lesion in the anterior pituitary. RESULTS Analysis of the LHX3 gene revealed homozygosity for a novel single-base-pair deletion in exon 2. This mutation leads to a frame shift predicted to result in the production of short, inactive LHX3 proteins. The results of in vitro translation experiments are consistent with this prediction. The parents of the patients are heterozygotes, indicating a recessive mode of action for the deletion allele. CONCLUSIONS The presence of a hypointense pituitary lesion and other clinical findings broadens the phenotype associated with LHX3 gene mutation.
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Affiliation(s)
- Amrit P S Bhangoo
- Pediatric Endocrinology Division, Infant's and Children's Hospital of Brooklyn at Maimonides, Brooklyn, New York 11219, USA
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Pals K, Vankelecom H, Denef C. Triiodothyronine expands the lactotroph and maintains the lactosomatotroph population, whereas thyrotrophin-releasing hormone augments thyrotroph abundance in aggregate cell cultures of postnatal rat pituitary gland. J Neuroendocrinol 2006; 18:203-16. [PMID: 16454804 DOI: 10.1111/j.1365-2826.2005.01404.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the present study, we used a three-dimensional pituitary cell culture system from early postnatal rats to examine the in vitro developmental potential of triiodothyronine (T3) and thyrotrophin-releasing hormone (TRH). Cell types were identified at the hormone mRNA level by single-cell reverse transcription-polymerase chain reaction and any change in abundance was further examined by immunofluorescence staining of the corresponding hormone protein. In aggregates from 14-day-old rats, long-term (12-16 days) treatment with T3 (0.5 nM) increased the abundance of cells expressing prolactin mRNA (PRLmRNA cells) by 2.5-fold and lowered that of nonhormonal cells and thyroid-stimulating hormone beta (TSHbeta)mRNA cells. The abundance of growth hormone (GH)mRNA cells decreased during culture compared to that in the freshly dispersed pituitary gland and T3 did not significantly affect this cell population. Cells coexpressing PRL mRNA and GH mRNA virtually disappeared during culture but reappeared in the presence of T3. T3 increased the abundance of PRL-immunoreactive (ir) cells in aggregates from 14-day-old rats, as well as in aggregates from newborn and 1-week-old rats. As estimated by bromodeoxyuridine (BrdU) labelling, a 3-day treatment with T3 enhanced the number of PRL-ir cells that had incorporated BrdU, but did not yet expand the total population of PRL-ir cells. Long-term treatment with TRH (100 nM) did not affect the proportion of PRLmRNA or GHmRNA cells, but consistently increased the proportional number of TSHbeta(mRNA) and TSHbeta-ir cells. The present data confirm the findings obtained in recent in vivo loss of function genetic studies suggesting that T3 plays a prominent role in postnatal expansion of the lactotroph population and that TRH is important for thyrotroph development. The data suggest that the effect of T3 is brought about by a direct action on the pituitary gland through a cell proliferation mechanism. T3 also appears to support the lactosomatotroph population. In view of the established theory that lactotrophs develop from GH-expressing progenitor cells and that this is a post mitotic event, we propose that T3 is mitogenic for GHmRNA cells that lack GH-ir material and that transdifferentiate into PRL-ir cells, but that a pathway of PRL cell development from mitotic nonhormonal cell progenitors may also be involved.
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Affiliation(s)
- K Pals
- Laboratory of Cell Pharmacology, University of Leuven (K.U.Leuven), Medical School, Campus Gasthuisberg (O & N), B-3000, Leuven, Belgium
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Ellestad LE, Carre W, Muchow M, Jenkins SA, Wang X, Cogburn LA, Porter TE. Gene expression profiling during cellular differentiation in the embryonic pituitary gland using cDNA microarrays. Physiol Genomics 2006; 25:414-25. [PMID: 16493019 DOI: 10.1152/physiolgenomics.00248.2005] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The anterior pituitary is comprised of five major hormone-secreting cell types that differentiate during embryonic development in a temporally distinct manner. Microarrays containing 5,128 unique cDNAs expressed in the chicken neuroendocrine system were produced and used to identify genes with potential involvement in the onset of thyroid-stimulating hormone beta-subunit (TSHbeta), growth hormone (GH), and prolactin (PRL) mRNA during embryonic development. We identified 352 cDNAs that were differentially expressed (P < or = 0.05) on embryonic day 10 (e10), e12, e14, or e17, the period of thyrotroph, somatotroph, and lactotroph differentiation. Self-organizing maps were used to identify genes that may function to initiate hormone gene transcription. Consistent with cellular ontogeny, TSHbeta mRNA increased steadily between e10 and e17, GH mRNA increased between e12 and e17, and PRL mRNA did not increase until e17. Expression of 141 genes increased in a manner similar to TSHbeta mRNA, and 64 genes decreased between e10 and e17. Although genes with these expression profiles are likely involved in development of the pituitary gland as a whole, some of these could be specifically associated with thyrotroph differentiation. Similarly, the expression profiles of 69 and 61 genes indicate a potential involvement in the induction of GH and PRL mRNA, respectively. Quantitative real-time RT-PCR was used to confirm microarray results for 31 genes. This is the first study to evaluate changes in anterior pituitary gene expression during embryonic development of any species using microarrays, and numerous transcription factors and signaling molecules not previously implicated in pituitary development were identified.
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Affiliation(s)
- Laura E Ellestad
- Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland 20742, USA.
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