Koster Kevin P, Yoshii Akira
Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, United States.
Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, United States.
Front Synaptic Neurosci. 2019 Aug 29;11:25. doi: 10.3389/fnsyn.2019.00025. eCollection 2019.
Protein palmitoylation is the post-translational, reversible addition of a 16-carbon fatty acid, palmitate, to proteins. Protein palmitoylation has recently garnered much attention, as it robustly modifies the localization and function of canonical signaling molecules and receptors. Protein depalmitoylation, on the other hand, is the process by which palmitic acid is removed from modified proteins and contributes, therefore, comparably to palmitoylated-protein dynamics. Palmitoylated proteins also require depalmitoylation prior to lysosomal degradation, demonstrating the significance of this process in protein sorting and turnover. Palmitoylation and depalmitoylation serve as particularly crucial regulators of protein function in neurons, where a specialized molecular architecture and cholesterol-rich membrane microdomains contribute to synaptic transmission. Three classes of depalmitoylating enzymes are currently recognized, the acyl protein thioesterases, α/β hydrolase domain-containing 17 proteins (ABHD17s), and the palmitoyl-protein thioesterases (PPTs). However, a clear picture of depalmitoylation has not yet emerged, in part because the enzyme-substrate relationships and specific functions of depalmitoylation are only beginning to be uncovered. Further, despite the finding that loss-of-function mutations affecting palmitoyl-protein thioesterase 1 (PPT1) function cause a severe pediatric neurodegenerative disease, the role of PPT1 as a depalmitoylase has attracted relatively little attention. Understanding the role of depalmitoylation by PPT1 in neuronal function is a fertile area for ongoing basic science and translational research that may have broader therapeutic implications for neurodegeneration. Here, we will briefly introduce the rapidly growing field surrounding protein palmitoylation and depalmitoylation, then will focus on the role of PPT1 in development, health, and neurological disease.
蛋白质棕榈酰化是指在翻译后将16碳脂肪酸棕榈酸可逆地添加到蛋白质上。最近,蛋白质棕榈酰化备受关注,因为它能有力地改变经典信号分子和受体的定位及功能。另一方面,蛋白质去棕榈酰化是指从修饰后的蛋白质中去除棕榈酸的过程,因此它对棕榈酰化蛋白质的动态变化也有类似的作用。棕榈酰化蛋白质在溶酶体降解之前也需要去棕榈酰化,这表明该过程在蛋白质分选和周转中具有重要意义。在神经元中,棕榈酰化和去棕榈酰化是蛋白质功能的特别关键的调节因子,其中特殊的分子结构和富含胆固醇的膜微区有助于突触传递。目前已确认有三类去棕榈酰化酶,即酰基蛋白硫酯酶、含α/β水解酶结构域的17蛋白(ABHD17s)和棕榈酰蛋白硫酯酶(PPTs)。然而,去棕榈酰化的清晰图景尚未形成,部分原因是去棕榈酰化的酶-底物关系和具体功能才刚刚开始被揭示。此外,尽管发现影响棕榈酰蛋白硫酯酶1(PPT1)功能的功能丧失突变会导致严重的儿童神经退行性疾病,但PPT1作为去棕榈酰化酶的作用相对较少受到关注。了解PPT1介导的去棕榈酰化在神经元功能中的作用是当前基础科学和转化研究的一个活跃领域,可能对神经退行性疾病具有更广泛的治疗意义。在这里,我们将简要介绍围绕蛋白质棕榈酰化和去棕榈酰化迅速发展的领域,然后将重点关注PPT1在发育、健康和神经疾病中的作用。