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: 10025263
• 负责人: Ana Paula de Abreu e Silva Metzger
• 金额: $ 24.89万
• 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/10025263
• 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，但在儿童期受到抑制。再- HPG轴的激活导致青春期的开始。调节GnRH分泌的精确机制， 在婴儿期和儿童期限制HPG轴，随后触发青春期的开始， 难以捉摸。青春期的时间与随后疾病的风险有关，关键是要确定哪些因素 青春期的开始遗传、营养和环境因素之间的复杂相互作用影响着 青春期开始我们最近发现，在中枢神经系统疾病家族中，MKRN 3的功能缺失突变 性早熟（CPP）。MKRN 3位于染色体15 q上，并且是母系印记的，仅表达 来自父系遗传的等位基因MKRN 3基因突变与CPP的关联是无可争议的; 然而，MKRN 3中的印迹异常作为青春期疾病的原因的可能性尚未被证实。 探讨了MKRN 3的表观遗传调节可能是环境线索和青春期时间之间的联系。这 该提案将调查青春期发育期间的MKRN 3印迹概况，并确定MKRN 3是否 印记异常与青春期疾病有关;并研究 MKRN 3调节GnRH分泌。为此，提出了四个不同但互补的具体目标。 该提案的指导阶段将在布里格姆的乌苏拉·凯泽博士的监督下进行， 妇女医院/哈佛医学院。K99辅导阶段的目标是：1）调查 MKRN 3在人类生命不同阶段的甲基化谱，并确认小鼠中的甲基化模式 组织;和2）表征MKRN 3调节GnRH的细胞和分子机制 体外分泌。该培训将提供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MKRN 3印迹谱的阐明 了解MKRN 3在下丘脑神经元中的作用将为研究MKRN 3在下丘脑神经元中的作用提供坚实的基础。 知识过渡到独立的R 00阶段的奖励。根据以往的经验， R 00独立阶段的目的是：3）调查MKRN 3印迹异常是否与 4）将MKRN 3的作用机制的研究扩展到体内小鼠模型。 该奖项包括一个结构良好的培训计划，其中包括课程工作和研讨会学习 经验该项目的完成将导致更好地了解MKRN 3在以下方面的分子作用： 促性腺激素释放激素分泌调节和推进我们对MKRN 3印迹的基础知识。的 成功完成这项提案的目标将为神经内分泌调节带来新的见解， 促性腺激素释放激素分泌，使我能够建立我的职业生涯作为一个成功的独立翻译研究者。