以定量磷酸化蛋白質體學探討鋅指蛋白ZNF322A在人類肺癌A549細胞中的調控路徑

Quantitative Phosphoproteomic Analysis Reveals the Regulatory Pathways of ZNF322A in Human Lung Adenocarcinoma A549 Cells

陳瑋庭(Wei-Ting Chen)

指導教授 ： 阮雪芬

國立臺灣大學/生命科學院/生命科學系/碩士(2015年)

https://doi.org/10.6342/NTU.2015.00486

摘要

鋅指蛋白322A (ZNF322A) 是屬於C2H2型鋅指蛋白家族並為一種轉錄因子。近年的研究指出ZNF322A在肺癌病患與腫瘤發生有關，是一個致癌基因。然而，ZNF322A在肺癌細胞中所調控的下游訊息傳遞路徑尚未被了解透徹。我們利用羥基酸修正金屬氧化物層析(hydroxy acid-modified metal oxide chromatography, HAMMOC)及奈米級液相層析與串聯式質譜儀(nanoLC-MS/MS)闡述了在肺癌細胞中由ZNF322A下游訊息引發的蛋白質磷酸化現象。在本研究中，共發現了4501個磷酸化位置對應於1309個磷酸化蛋白質，其中有443個磷酸化位置顯著被ZNF322A所調控。利用生物資訊學研究法，包含功能富集分析，生物網路分析及磷酸化基序分析，我們提出先前尚未發現ZNF322A與哺乳動物雷帕黴素靶蛋白(mTOR)的訊息路徑及細胞自噬作用的相關性，並且展現了ZNF322A在癌症形成與細胞骨架調節等腫瘤相關形成過程中扮演重要的角色。本研究不只給予ZNF322A在後轉譯階層的分子調控資訊，也提供肺癌治療上一個新的方向。

關鍵字

鋅指蛋白 ； 致癌基因 ； 磷酸化蛋白質體學 ； 羥基酸修正金屬氧化物層析 ； 自噬作用

並列摘要

ZNF322A is a transcription factor and belongs to the krüppel C2H2-type zinc-finger protein family. Recently, ZNF322A was reported as a potential oncogene in lung cancer patients and is critical for tumorigenesis. However, ZNF322A-mediated downstream signaling pathways in lung cancer cells remain unclear. Using hydroxy acid-modified metal oxide chromatography (HAMMOC) and nanoscale liquid chromatography–tandem MS (nanoLC-MS/MS), we examined protein phosphorylation induced by ZNF322A signaling in lung cancer A549 cells. We identified 4501 phosphorylation sites in 1309 phosphoproteins. Among these phosphosites, 443 were significantly changed in response to ZNF322A silencing. Using bioinformatics approaches including functional enrichments, network analysis and phosphorylation motif analysis, we highlighted a previously unidentified ZNF322A-mTOR signaling pathway and autophagic process. On the other hand, we demonstrated that ZNF322A plays an important role in cancer progression such as cytoskeleton regulation and tumor formation-associated process. This study not only gives new information about the molecular regulation by ZNF322A at post-translational level, but also provides a resource for the study of lung cancer therapy.

並列關鍵字

Zinc-finger protein ； oncogene ； phosphoproteome ； HAMMOC ； autophagy

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