MKRN3 imprinting, regulation, and action in the control of puberty

MKRN3 印记、调节和控制青春期的作用

• 批准号: 10021765
• 负责人: Ana Paula de Abreu e Silva Metzger
• 金额: $ 24.86万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-30 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10021765
• 关键词: 15q; Adult; Alleles; Award; Candidate Disease Gene; Cell Line; Cell Nucleus; Child; Childhood; Chromosomes; Complement; Complex; Cues; DNA Methylation; DNA Sequence Alteration; Data; Data Analyses; Defect; Delayed Puberty; Development; Diagnosis; Disease; Embryo; Environmental Risk Factor; Expression Profiling; Family; Frequencies; Gene Expression; Genetic; Genetic Techniques; Goals; Gonadotropin Hormone Releasing Hormone; Hormone secretion; Hospitals; Human; Hypothalamic structure; In Vitro; Inherited; Investigation; KISS1 gene; Klinefelter' s Syndrome; Knowledge; Learning; Life; Link; Measures; Mentors; Methylation; Molecular; Molecular Genetics; Mus; Neonatal; Neurons; Neurosecretory Systems; Nutritional; Pathway interactions; Patients; Phase; Physicians; Physiologic pulse; Precocious Puberty; Puberty; Regulation; Reproduction; Research; Risk; Role; Scientist; Sequence Analysis; Structure; Supervision; Tissues; Training; Training Programs; Translating; Vocational Guidance; Woman; Work; base; bisulfite; career; cohort; epigenetic regulation; experience; experimental study; genetic association; hypothalamic pituitary gonadal axis; imprint; in vivo; in vivo Model; induced pluripotent stem cell; infancy; insight; knock-down; loss of function mutation; maternal imprint; medical schools; methylation pattern; mouse model; novel; physical process; psychologic; pubertal timing; tool; transcriptome sequencing; translational scientist; ubiquitin-protein ligase

ABSTRACT Puberty and reproduction are controlled by the hypothalamic-pituitary-gonadal (HPG) axis. The HPG axis is active during the embryonic and neonatal stages of human life but then suppressed during childhood. The re- activation of HPG axis results in puberty initiation. The precise mechanisms that regulate GnRH secretion to constrain the HPG axis during infancy and childhood and subsequently trigger the initiation of puberty remain elusive. The timing of puberty is associated with risks of subsequent disease and it is crucial to identify what elicits puberty initiation. Complex interactions among genetic, nutritional, and environmental factors influence pubertal initiation. We have recently identified loss-of-function mutations in MKRN3 in families with central precocious puberty (CPP). MKRN3 is located on chromosome 15q and is maternally imprinted, expressed only from the paternally inherited allele. The association of genetic mutations in MKRN3 with CPP is indisputable; however, the possibility of imprinting abnormalities in MKRN3 as a cause of pubertal disorders has not been explored. Epigenetic regulation of MKRN3 may be a link between environmental cues and pubertal timing. This proposal will investigate the MKRN3 imprinting profile during pubertal development and determine if MKRN3 imprinting abnormalities are associated with pubertal disorders; and study the molecular mechanisms by which MKRN3 regulates GnRH secretion. To this end, four distinct but complementary specific aims are proposed. The mentored phase of the proposal will be carried out under Dr. Ursula Kaiser's supervision at Brigham and Women's Hospital/Harvard Medical School. The aims of the K99 mentored phase are to: 1) Investigate the MKRN3 methylation profile in different phases of human life and confirm the methylation pattern in mouse tissues; and 2) Characterize the cellular and molecular mechanisms by which MKRN3 regulates GnRH secretion in vitro. This training will provide expertise in DNA methylation studies, in hiPSC experiments, and in RNA-Seq data analysis. The elucidation of the MKRN3 imprinting profile during normal pubertal development and an understanding of the actions of MKRN3 in hypothalamic neurons will provide a strong base of knowledge for the transition to the independent R00 phase of the award. Building on previous experience, the aims of the R00 independent phase are to: 3) Investigate if abnormalities in MKRN3 imprinting are associated with pubertal disorders; 4) Extend investigation of mechanisms of action of MKRN3 to in vivo mouse models. This award includes a well-structured training program that includes course work and seminar learning experiences. Completion of this project will lead to a better understanding of the molecular roles of MKRN3 in the regulation of GnRH secretion and advance our fundamental knowledge of MKRN3 imprinting. The successful completion of the aims of this proposal will bring new insights in the neuroendocrine regulation of GnRH secretion and enable me to establish my career as a successful independent translational investigator.

摘要 青春期和生殖由下丘脑-垂体-性腺(HPG)轴控制。HPG轴是 在人类生命的胚胎和新生儿阶段活跃，但在童年时被抑制。再一次- HPG轴的激活导致青春期的启动。调节促性腺激素释放激素分泌的精确机制 在婴儿期和儿童期抑制HPG轴，随后触发青春期残留的启动 难以捉摸。青春期的时间与后续疾病的风险有关，确定什么是至关重要的 引发了青春期的萌发。遗传、营养和环境因素之间复杂的相互作用影响 青春期启蒙。我们最近在中枢神经系统疾病家系中发现了MKRN3功能缺失突变。 性早熟(CPP)。MKRN3位于染色体15q上，为母系印记，仅表达 来自父系遗传的等位基因。MKRN3基因突变与CPP的相关性是无可争辩的； 然而，MKRN3的印记异常作为青春期疾病的原因的可能性尚未得到证实 探索过了。MKRN3的表观遗传调控可能是环境线索和青春期时机之间的联系。这 该提案将调查青春期发育过程中MKRN3的印迹分布，并确定MKRN3是否 印记异常与青春期疾病有关；并研究其分子机制 MKRN3调节GnRH的分泌。为此，提出了四个截然不同但相辅相成的具体目标。 提案的指导阶段将在布里格姆大学的Ursula Kaiser博士的监督下进行 妇女医院/哈佛医学院。K99指导阶段的目标是：1)调查 人类生命不同阶段MKRN3甲基化图谱及小鼠甲基化模式的确定 2)MKRN3调节GnRH的细胞和分子机制 体外分泌。这项培训将提供DNA甲基化研究、HiPSC实验和 RNA-Seq数据分析。正常青春期发育过程中MKRN3基因印迹图谱的阐明 而了解MKRN3在下丘脑神经元中的作用将为 关于过渡到独立R00奖项阶段的知识。基于以前的经验， R00独立阶段的目的是：3)调查MKRN3印迹中的异常是否与 4)将MKRN3作用机制的研究扩展到活体小鼠模型。 该奖项包括一个结构良好的培训计划，其中包括课程作业和研讨会学习。 经历。该项目的完成将有助于更好地理解MKRN3在人类免疫系统中的分子作用 调节GnRH的分泌，提高我们对MKRN3印迹的基础知识。这个 这项提案的目标的成功完成将带来对神经内分泌调节的新见解 GnRH分泌，并使我能够建立我的职业生涯作为一个成功的独立翻译调查员。