当前位置: X-MOL 学术BBA Biomembr. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Proteasome-dependent protein quality control of the peroxisomal membrane protein Pxa1p.
Biochimica et Biophysica Acta (BBA) - Biomembranes ( IF 2.8 ) Pub Date : 2020-05-13 , DOI: 10.1016/j.bbamem.2020.183342
S Devarajan 1 , M Meurer 2 , C W T van Roermund 3 , X Chen 1 , E H Hettema 4 , S Kemp 3 , M Knop 5 , C Williams 1
Affiliation  

Peroxisomes are eukaryotic organelles that function in numerous metabolic pathways and defects in peroxisome function can cause serious developmental brain disorders such as adrenoleukodystrophy (ALD). Peroxisomal membrane proteins (PMPs) play a crucial role in regulating peroxisome function. Therefore, PMP homeostasis is vital for peroxisome function. Recently, we established that certain PMPs are degraded by the Ubiquitin Proteasome System yet little is known about how faulty/non-functional PMPs undergo quality control. Here we have investigated the degradation of Pxa1p, a fatty acid transporter in the yeast Saccharomyces cerevisiae. Pxa1p is a homologue of the human protein ALDP and mutations in ALDP result in the severe disorder ALD. By introducing two corresponding ALDP mutations into Pxa1p (Pxa1MUT), fused to mGFP, we show that Pxa1MUT-mGFP is rapidly degraded from peroxisomes in a proteasome-dependent manner, while wild type Pxa1-mGFP remains relatively stable. Furthermore, we identify a role for the ubiquitin ligase Ufd4p in Pxa1MUT-mGFP degradation. Finally, we establish that inhibiting Pxa1MUT-mGFP degradation results in a partial rescue of Pxa1p activity in cells. Together, our data demonstrate that faulty PMPs can undergo proteasome-dependent quality control. Furthermore, our observations may provide new insights into the role of ALDP degradation in ALD.

中文翻译:

过氧化物酶体膜蛋白Pxa1p的蛋白酶体依赖性蛋白质量控制。

过氧化物酶体是在许多代谢途径中起作用的真核细胞器,并且过氧化物酶体功能的缺陷会引起严重的发育性脑疾病,例如肾上腺白质营养不良(ALD)。过氧化物酶体膜蛋白(PMP)在调节过氧化物酶体功能中起关键作用。因此,PMP稳态对于过氧化物酶体功能至关重要。最近,我们确定了泛素蛋白酶体系统会降解某些PMP,但对有缺陷/无功能的PMP如何进行质量控制所知甚少。在这里,我们研究了酵母Saccharomyces cerevisiae中脂肪酸转运蛋白Pxa1p的降解。Pxa1p是人类蛋白质ALDP的同源物,ALDP中的突变会导致严重的ALD疾病。通过将两个对应的ALDP突变引入与mGFP融合的Pxa1p(Pxa1MUT),我们表明,Pxa1MUT-mGFP是由过氧化物酶体以蛋白酶体依赖性方式快速降解的,而野生型Pxa1-mGFP则保持相对稳定。此外,我们确定泛素连接酶Ufd4p在Pxa1MUT-mGFP降解中的作用。最后,我们建立抑制Pxa1MUT-mGFP降解导致细胞中Pxa1p活性的部分挽救。在一起,我们的数据表明,有缺陷的PMP可以进行蛋白酶体依赖的质量控制。此外,我们的观察结果可能为ALDP降解在ALD中的作用提供新的见解。我们建立抑制Pxa1MUT-mGFP降解导致细胞中Pxa1p活性的部分挽救。在一起,我们的数据表明,有缺陷的PMP可以进行蛋白酶体依赖的质量控制。此外,我们的观察结果可能为ALDP降解在ALD中的作用提供新的见解。我们建立抑制Pxa1MUT-mGFP降解导致细胞中Pxa1p活性的部分挽救。在一起,我们的数据表明,有缺陷的PMP可以进行蛋白酶体依赖的质量控制。此外,我们的观察结果可能为ALDP降解在ALD中的作用提供新的见解。
更新日期:2020-05-13
down
wechat
bug