FBP1(Fructose-1,6-bisphosphatase 1)是一种关键的代谢酶,在葡萄糖新生(Gluconeogenesis)途径中起着限速酶的作用。葡萄糖新生是指非糖物质(如氨基酸、乳酸、甘油)在肝脏中转化为葡萄糖的过程,是维持血糖水平的重要机制。FBP1通过催化1,6-二磷酸果糖转化为果糖-6-磷酸,从而促进葡萄糖新生。FBP1的表达和活性受到多种因素的调控,包括胰岛素、糖皮质激素、饥饿状态等。
FBP1的功能不仅限于其酶活性,还涉及非酶活性的细胞过程。FBP1的核定位信号(NLS)使其能够进入细胞核,并在那里参与基因表达的调控。研究表明,FBP1能够与过氧化物酶体增殖物激活受体α(PPARα)结合,并作为蛋白磷酸酶,去磷酸化组蛋白H3T11,从而抑制PPARα介导的β-氧化基因表达,进而影响肿瘤生长[2]。
FBP1的缺失或功能异常与多种疾病的发生发展密切相关。在肝脏肿瘤中,FBP1的表达普遍下调,其缺失导致肝脏代谢失衡,促进肿瘤进展。FBP1的缺失还会导致肝星状细胞(HSCs)的激活和衰老,并释放衰老相关的分泌表型(SASP),进一步促进肿瘤生长[1]。此外,FBP1的缺失还会导致胰岛素信号通路的异常激活,引发胰岛素超敏反应,导致肝肿大、肝脂肪变性和高脂血症等病理变化[3]。
FBP1的表达和功能还受到表观遗传调控的影响。研究发现,FBP1基因的启动子区域存在DNA甲基化,其甲基化水平与多种疾病的发生发展相关。例如,在非小细胞肺癌(NSCLC)中,FBP1基因启动子区域的甲基化水平升高与患者的总体生存率呈负相关[8]。此外,FBP1的表达还受到微小RNA(miRNA)的调控。例如,miR-26通过抑制FBP1的表达,减缓动脉粥样硬化的发生发展[4]。
FBP1的缺失或功能异常还与一些遗传性疾病相关。例如,FBP1的突变导致FBP1酶活性降低,引发FBP1缺乏症,表现为低血糖、酮症、代谢性酸中毒等症状[5,7]。此外,FBP1的突变还与肾细胞癌的发生发展相关,FBP1的核功能缺失导致缺氧诱导因子(HIF)的表达上调,进而促进肿瘤生长[6]。
综上所述,FBP1是一种重要的代谢酶,其功能不仅限于葡萄糖新生途径,还涉及非酶活性的细胞过程,如基因表达调控、胰岛素信号通路调节等。FBP1的表达和功能受到多种因素的调控,包括胰岛素、糖皮质激素、饥饿状态、DNA甲基化、miRNA等。FBP1的缺失或功能异常与多种疾病的发生发展密切相关,包括肝脏肿瘤、胰岛素超敏反应、FBP1缺乏症、肾细胞癌等。对FBP1的深入研究有助于我们更好地理解代谢调控与疾病发生发展的关系,为相关疾病的治疗和预防提供新的思路和策略。
参考文献:
1. Li, Fuming, Huangyang, Peiwei, Burrows, Michelle, Li, Bo, Simon, M Celeste. 2020. FBP1 loss disrupts liver metabolism and promotes tumorigenesis through a hepatic stellate cell senescence secretome. In Nature cell biology, 22, 728-739. doi:10.1038/s41556-020-0511-2. https://pubmed.ncbi.nlm.nih.gov/32367049/
2. Wang, Zheng, Li, Min, Jiang, Hongfei, Xu, Daqian, Lu, Zhimin. 2022. Fructose-1,6-bisphosphatase 1 functions as a protein phosphatase to dephosphorylate histone H3 and suppresses PPARα-regulated gene transcription and tumour growth. In Nature cell biology, 24, 1655-1665. doi:10.1038/s41556-022-01009-4. https://pubmed.ncbi.nlm.nih.gov/36266488/
3. Gu, Li, Zhu, Yahui, Watari, Kosuke, Simon, M Celeste, Karin, Michael. 2023. Fructose-1,6-bisphosphatase is a nonenzymatic safety valve that curtails AKT activation to prevent insulin hyperresponsiveness. In Cell metabolism, 35, 1009-1021.e9. doi:10.1016/j.cmet.2023.03.021. https://pubmed.ncbi.nlm.nih.gov/37084733/
4. Chen, Wujun, Wu, Xiaolin, Hu, Jianxia, Wang, Jie, Xing, Dongming. 2024. The translational potential of miR-26 in atherosclerosis and development of agents for its target genes ACC1/2, COL1A1, CPT1A, FBP1, DGAT2, and SMAD7. In Cardiovascular diabetology, 23, 21. doi:10.1186/s12933-024-02119-z. https://pubmed.ncbi.nlm.nih.gov/38195542/
5. Liang, Xiaoyan, Liu, Xiaoliang, Li, Wenjing, Lai, Guangrui, Zhao, Yanyan. 2023. A novel variant in the FBP1 gene causes fructose-1,6-bisphosphatase deficiency through increased ubiquitination. In Archives of biochemistry and biophysics, 742, 109619. doi:10.1016/j.abb.2023.109619. https://pubmed.ncbi.nlm.nih.gov/37142076/
6. Ning, Xiang-Hui, Li, Teng, Gong, Yan-Qing, Guo, Ying-Lu, Gong, Kan. 2016. Association between FBP1 and hypoxia-related gene expression in clear cell renal cell carcinoma. In Oncology letters, 11, 4095-4098. doi:. https://pubmed.ncbi.nlm.nih.gov/27313747/
7. Faiyaz-Ul-Haque, Muhammad, Al-Owain, Mohammed, Al-Dayel, Fouad, Peltekova, Iskra, Zaidi, Syed H E. 2009. Novel FBP1 gene mutations in Arab patients with fructose-1,6-bisphosphatase deficiency. In European journal of pediatrics, 168, 1467-71. doi:10.1007/s00431-009-0953-9. https://pubmed.ncbi.nlm.nih.gov/19259699/
8. Dong, Yao, Huaying, Sheng, Danying, Wan, Xiaojiang, Sun, Jianguo, Feng. 2018. Significance of Methylation of FBP1 Gene in Non-Small Cell Lung Cancer. In BioMed research international, 2018, 3726091. doi:10.1155/2018/3726091. https://pubmed.ncbi.nlm.nih.gov/29984231/