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: 10249285
• 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/10249285
• 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; 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; Sexual Reproduction; 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.

抽象的 青春期和繁殖由下丘脑 - 垂体 - 甲状腺（HPG）轴控制。 HPG轴为 在人类生活的胚胎和新生儿阶段活跃，但在童年时期被抑制。那里- HPG轴的激活会导致青春期起始。调节GnRH分泌的确切机制 在婴儿期和儿童期限制HPG轴，然后触发青春期的开始 难以捉摸。青春期的时机与随后疾病的风险有关，至关重要 引起青春期开始。遗传，营养和环境因素之间的复杂相互作用影响 青春期的启动。我们最近确定了中央家族中MKRN3的功能丧失突变 早熟青春期（CPP）。 MKRN3位于15q染色体上，在母亲印刷，仅表示 从亲子遗传的等位基因。 MKRN3中的遗传突变与CPP的关联是无可争议的。 但是，将MKRN3烙印为青春期疾病的原因的可能性尚未 探索。 MKRN3的表观遗传调节可能是环境线索与青春期时机之间的联系。这 提案将在青春期开发过程中调查MKRN3烙印概况，并确定MKRN3是否 烙印异常与青春期疾病有关；并研究分子机制 MKRN3调节GNRH分泌。为此，提出了四个不同但互补的特定目标。 该提案的指导阶段将根据Ursula Kaiser博士在Brigham的监督和 妇女医院/哈佛医学院。 K99指导阶段的目的是：1）调查 MKRN3甲基化剖面在人类生命的不同阶段，并确认小鼠的甲基化模式 组织； 2）表征MKRN3调节GnRH的细胞和分子机制 体外分泌。该培训将在DNA甲基化研究，HIPSC实验和 RNA-seq数据分析。在正常的青春期开发过程中，MKRN3烙印概况阐明 对MKRN3在下丘脑神经元中的作用的理解将提供强大的基础 过渡到奖励独立R00阶段的知识。以先前的经验为基础 R00独立阶段的目的是：3）调查MKRN3印迹中的异常是否相关 有青春期疾病； 4）将MKRN3作用机理扩展到体内小鼠模型。 该奖项包括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。该项目的完成将使人们更好地了解MKRN3在 GNRH分泌的调节并提高了我们对MKRN3印迹的基本知识。这 成功完成该提案的目标将为神经内分泌调节带来新的见解 GNRH分泌物，使我能够建立自己的职业生涯，成为成功的独立翻译调查员。