Regulation of human skin homeostasis by histone arginine methylation regulators

描述（由申请人提供）：表皮稳态在许多人类皮肤病中被破坏，包括牛皮癣、慢性伤口和癌症。通过表观遗传调控因子，特别是组蛋白精氨酸甲基转移酶PRMT1和组蛋白精氨酸去甲基化酶JMJD6，增加对表皮生长和分化的基因调控的理解，是该培训计划的中心重点。首先，我们将定义组蛋白精氨酸去甲基化酶JMJD6在表皮稳态中的作用，该酶使组蛋白H4精氨酸3二甲基化（H4R3me2）去甲基化。在我们的初步研究中，我们观察到组蛋白标记H4R3me2在人角质形成细胞分化过程中受到动态调节。在培养的原代人角质形成细胞中，H4R3me2组蛋白精氨酸去甲基化酶JMJD6的缺失会损害钙诱导的分化。为了扩展这些发现，我们将利用我们实验室建立的人体组织再生模型，在完整组织水平上确定JMJD6在正常人类表皮组织稳态中的作用。我们还将描述JMJD6在表皮生长和分化中的作用。其次，我们将阐明组蛋白精氨酸甲基转移酶PRMT1在表皮肿瘤早期进展中的作用，该酶能甲基化组蛋白H4R3。我们最近观察到PRMT1是抑制表皮分化所必需的。多个经过验证的短发夹rna （shrna）丢失PRMT1会抑制增殖并诱导分化标记基因的表达。此外，PRMT1在多种人类癌症组织中过表达。由于肿瘤进化的第一步以生长和分化的改变为特征，我们假设PRMT1是组织向肿瘤发展所必需的。因此，我们将确定PRMT1在表皮肿瘤转化中的作用。在计划的资助期结束时，我们希望能够确定JMJD6和PRMT1基因调控蛋白在控制表皮增殖和分化中的机制作用，为未来开发以表皮稳态破坏为特征的人类疾病的新治疗策略奠定基础。

DESCRIPTION (provided by applicant): Epidermal homeostasis is disrupted in a host of human skin diseases, including psoriasis, chronic wounds, and cancer. Increased understanding of the gene regulatory control of epidermal growth and differentiation by epigenetic regulators, specifically histone arginine methyltransferase PRMT1 and histone arginine demethylase JMJD6, is the central focus of this training plan. First, we will define the role of the histone arginine demethylase JMJD6, which demethylates histone H4 Arginine 3 dimethylation (H4R3me2), in epidermal homeostasis. In our preliminary studies, we observed that the histone mark H4R3me2 is dynamically regulated during human keratinocyte differentiation. In cultured primary human keratinocytes, loss of the H4R3me2 histone arginine demethylase JMJD6 impairs calcium- induced differentiation. To extend these findings, we will define the role of JMJD6 in normal human epidermal tissue homeostasis at the level of intact tissue, leveraging the human tissue regeneration models established in our laboratory. We will also characterize the action of JMJD6 in epidermal growth and differentiation. Second, we will elucidate the role of the histone arginine methyltransferase PRMT1, which methylates histone H4R3, in early progression towards epidermal neoplasia. We recently observed that PRMT1 is required to suppress epidermal differentiation. Loss of PRMT1 by multiple validated short-hairpin RNAs (shRNAs) inhibits proliferation and induces differentiation marker gene expression. Furthermore, PRMT1 is overexpressed in multiple human cancer tissues. Since the first steps in tumor evolution is characterized by alterations in growth and differentiation, we hypothesize that PRMT1 is required for tissue progression toward neoplasia. We will therefore define the role of PRMT1 in epidermis undergoing neoplastic transformation. At the end of the proposed funding period, we hope to have characterized the mechanistic actions of both JMJD6 and PRMT1 gene regulatory proteins in the control of epidermal proliferation and differentiation as a foundation for the future development of new treatment strategies for human disorders of characterized by disrupted epidermal homeostasis. PUBLIC HEALTH RELEVANCE: Epidermal proliferation and differentiation are subject to precise spatial and temporal control to achieve normal skin homeostasis, a balance that is disrupted in a wide spectrum of common human skin diseases including psoriasis, chronic wounds and cancer. Epigenetic regulators, such as histone modifying enzymes, play critical roles in these processes by controlling gene expression through multiple cell division cycles without altering DNA nucleotide sequence. Leveraging the strength of human tissue models established in our laboratory, specifically the normal human epidermal tissue regeneration model and the human skin tissue neoplasm model, this training plan is directed at understanding the gene regulatory mechanisms governing epidermal homeostasis by epigenetic regulators, providing therapeutic information for human epithelial disorders.