基因Ppt1,也称为palmitoyl-protein thioesterase 1,是一种重要的酶,主要在溶酶体中发挥作用。该酶负责从S-棕榈酰化蛋白中去除棕榈酸,从而促进这些蛋白的降解和清除。Ppt1的缺失或功能障碍与多种疾病有关,包括神经变性疾病、癌症和视网膜变性等。
Ppt1在神经变性疾病中发挥着重要作用。例如,神经元蜡样脂褐质沉积症(NCLs)是一类常见的神经退行性疾病,由PPT1和TPP1基因突变引起。研究表明,Ppt1缺陷导致溶酶体中棕榈酰化蛋白的积累,进而引发神经细胞死亡和功能障碍[2,4]。此外,Ppt1还参与调节溶酶体钙离子稳态,Ppt1缺失会导致溶酶体钙离子水平异常,进一步影响溶酶体的降解功能[6]。
在癌症领域,Ppt1的研究也取得了重要进展。研究表明,Ppt1在多种癌症中表达上调,并与不良预后相关。例如,在肝细胞癌(HCC)中,Ppt1阳性巨噬细胞浸润与患者生存率降低和预后不良相关[1]。Ppt1还通过影响巨噬细胞的免疫抑制转化和肿瘤微环境,促进肿瘤的发生和发展[1]。此外,Ppt1还参与调节口腔鳞状细胞癌(OSCC)细胞的生长和铁死亡,Ppt1的表达上调与OSCC患者的预后不良相关[3]。
Ppt1的研究还涉及到其他疾病,如视网膜变性。研究发现,PPT1基因的复杂结构变异与犬类非综合征性视网膜变性相关,这表明Ppt1在视网膜发育和功能维持中发挥着重要作用[5]。
综上所述,Ppt1是一种重要的溶酶体酶,参与调控棕榈酰化蛋白的降解和清除,并在多种疾病中发挥重要作用。Ppt1的缺失或功能障碍与神经变性疾病、癌症和视网膜变性等疾病的发生和发展密切相关。深入研究Ppt1的功能和机制,有助于为这些疾病的治疗和预防提供新的思路和策略。
参考文献:
1. Weng, Jialei, Liu, Shaoqing, Zhou, Qiang, Zhou, Chenhao, Ren, Ning. . Intratumoral PPT1-positive macrophages determine immunosuppressive contexture and immunotherapy response in hepatocellular carcinoma. In Journal for immunotherapy of cancer, 11, . doi:10.1136/jitc-2022-006655. https://pubmed.ncbi.nlm.nih.gov/37385725/
2. Sheth, Jayesh, Mistri, Mehul, Bhavsar, Riddhi, Shah, Raju, Sheth, Frenny. 2018. Batten disease: biochemical and molecular characterization revealing novel PPT1 and TPP1 gene mutations in Indian patients. In BMC neurology, 18, 203. doi:10.1186/s12883-018-1206-1. https://pubmed.ncbi.nlm.nih.gov/30541466/
3. Luo, Qingqiong, Hu, Sheng, Tang, Yijie, Yang, Dandan, Chen, Qilong. . PPT1 Promotes Growth and Inhibits Ferroptosis of Oral Squamous Cell Carcinoma Cells. In Current cancer drug targets, 24, 1047-1060. doi:10.2174/0115680096294098240123104657. https://pubmed.ncbi.nlm.nih.gov/38299399/
4. Kousi, Maria, Lehesjoki, Anna-Elina, Mole, Sara E. 2011. Update of the mutation spectrum and clinical correlations of over 360 mutations in eight genes that underlie the neuronal ceroid lipofuscinoses. In Human mutation, 33, 42-63. doi:10.1002/humu.21624. https://pubmed.ncbi.nlm.nih.gov/21990111/
5. Murgiano, Leonardo, Becker, Doreen, Torjman, Dina, Leeb, Tosso, Aguirre, Gustavo D. 2019. Complex Structural PPT1 Variant Associated with Non-syndromic Canine Retinal Degeneration. In G3 (Bethesda, Md.), 9, 425-437. doi:10.1534/g3.118.200859. https://pubmed.ncbi.nlm.nih.gov/30541930/
6. Mondal, Avisek, Appu, Abhilash P, Sadhukhan, Tamal, Liu, Aiyi, Mukherjee, Anil B. 2022. Ppt1-deficiency dysregulates lysosomal Ca++ homeostasis contributing to pathogenesis in a mouse model of CLN1 disease. In Journal of inherited metabolic disease, 45, 635-656. doi:10.1002/jimd.12485. https://pubmed.ncbi.nlm.nih.gov/35150145/