2021-01-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/702005基因體經常受各式威脅所損傷，導致基因體不穩定甚至遺傳疾病的發生。DNA損傷反應包括DNA損傷訊息傳導和修復，由ATR-Chk1和ATM-Chk2兩種激酶途徑經一連串磷酸化過程，防止基因體不穩定。新證據表明DNA損傷反應不單是磷酸化，其他轉譯後修飾亦參與其中。小泛素蛋白的修飾是一種必需的轉譯後修飾，可調節各種細胞功能。已知許多重要的DNA損傷調節因子都會被小泛素蛋白修飾，該修飾於DNA損傷反應扮演關鍵作用。若出現缺損，細胞會對DNA損傷更為敏感。然而，目前僅有少數小泛素蛋白連接酶被報導參與在DNA損傷反應。RanBP2 / Nup358是核孔複合物的一部分並具有小泛素蛋白連接酶活性，調節細胞質和核質間的運輸。核孔複合物亦與與染色質結構和DNA損傷修復有關。此外，核孔複合物的組成蛋白的突變或失調也與腫瘤發生有關。然而RanBP2與核孔複合物在DNA損傷反應 和腫瘤發生的詳細機制尚不清楚。我們研究專注在小泛素蛋白的修飾在DNA損傷反應的功能。初步實驗結果顯示RanBP2 可能參與調節DNA損傷反應。本研究計畫目標在闡明RanBP2與核孔複合物在基因體穩定性中的角色。研究將分成三階段來進行。目標一：了解核孔複合物如何調控ＤＮＡ損傷反應，目標二：探討ＤＮＡ損傷激酶ATR-ATM如何調控核孔複合物，目標三：釐清RanBP2磷酸化於核孔之功能。 Our genome is continuously insulted by a variety of threats that may lead to genomic instability and formation of numerous genetic disorders. The DNA damage response (DDR) is a complex of DNA damage signaling and repair network orchestrated by ATR-Chk1 and ATM-Chk2 kinase pathways that prevent genomic instability via a series of phosphorylation events. Emerging evidence has indicated that regulation of the DDR is not merely a phosphorylation event, several types of post- translational modifications are also required for the DDR. Protein modification by SUMO (small ubiquitin-like molecule) is an essential post-translational modification that regulates a wide range of cellular functions including the DDR. Many of the important DNA damage regulators such as ATR interacting protein (ATRIP), RPA70, and BRCA1 are known to be SUMOylated. SUMO modification of DDR proteins plays a critical role in either DNA damage sensing or DNA repair. Cells with SUMO defects in the DDR proteins are often sensitive to DNA damage agents. However, only a few SUMO E3 ligases have been identified to involve in the DDR. RanBP2/Nup358, a large protein with SUMO E3 ligase activity is part of nuclear pore complex (NPC) that mediates trafficking between cytoplasm and nucleoplasm. NPC is also involved in chromatin structure and DNA damage repair. Importantly, mutations or dysregulation of several key components of NPC are linked to tumorigenesis; however, the detail mechanisms of how RanBP2/NPC involved in the DDR and tumorigenesis are not well understood. Our lab is focusing on protein SUMOylation and the functions of SUMO pathway in the DDR. Built on solid preliminary data, we hypotheses that RanBP2 and NPC have a role in regulating the DDR and genomic stability. In this application, we propose to decipher the role of RanBP2 and NPC in genomic stability with the following three aims. Aim 1: To interrogate how RanBP2/NPC regulates the DDR. Aim 2: To interrogate regulation of RanBP2/NPC after genotoxic stress. Aim 3: To evaluate the phosphorylation of RanBP2 in NPC function.DNA損傷反應小泛素蛋白修飾核孔複合物基因體不穩定腫瘤ATRSUMOylationnuclear pore complexgenome instability