ABHD18通过脂肪酸的逐步水解来降解心脏脂蛋白
Mindong Ren1, Shiyu Chen1, Miriam L Greenberg2
1Department of Anesthesiology, New York University Grossman School of Medicine, New York, New York, USA.
The Journal of biological chemistry
|May 16, 2025
概括
阿尔法/β-基酶域18 (ABHD18) 被确定为难以捉摸的脂酶,可以分解心脏脂素 (CL). 这一发现澄清了CL重塑路径,突出了ABHD18的存在.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 心脏脂素 (CL) 是一种重要的线粒体脂素,具有复杂的脂肪酸重塑过程.
- 在酵母中,CL重塑涉及Cld1 (脂酶) 和Taz1 (转糖酶),但Cld1同类物以前是未知的.
- 在真核生物中保存了Taz1同类物,但相应的脂酶仍然难以捉摸.
研究的目的:
- 在其他生物体中识别酵母Cld1脂酶的功能同类.
- 阐明已识别的脂酶在心脂蛋白重塑和降解中的作用.
- 了解心脂蛋白脂酶和晶酶在维护线粒体功能中的相互作用.
主要方法:
- 作为心脂蛋白脂酶的α/β-酶域18 (ABHD18) 的功能性表征.
- 研究Abhd18在小鼠肌肉细胞中降低的效果.
- 在Drosophila模型中分析Abhd18无活化,包括缺少塔法津 (TAZ) 的.
- 使用13C同位素标记来测量心脂蛋白降解率.
主要成果:
- 鉴定出ABHD18是Cld1的功能性同类物,作为心脏脂蛋白脂酶起作用.
- 在小鼠细胞中,Abhd18 knockdown 降低了单解心素 (MLCL) 水平.
- 中的Abhd18无活化增加了心脂蛋白的丰富性,并降低了其降解率,特别是在TAZ缺乏模型中.
- 已经证明ABHD18能进一步去糖心脂蛋白,而不仅仅是去除单个脂肪酸.
结论:
- 在哺乳动物和昆虫中,ABHD18是负责CL分解的保存性心脂蛋白脂酶.
- 这项研究揭示了ABHD18作为心脏脂蛋白重塑通路中的关键酶,抵消TAZ的保护作用.
- 了解ABHD18的功能对于理解线粒体脂质稳态和相关疾病至关重要.
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