UEV-1 is an ubiquitin-conjugating enzyme variant that regulates glutamate receptor trafficking in C. elegans neurons.
UEV-1 is an ubiquitin-conjugating enzyme variant that regulates glutamate receptor trafficking in C. elegans neurons.
复制标题
DOI：
10.1371/journal.pone.0014291
复制
发表时间：
2010-12-13
期刊：
影响因子：
3.7
通讯作者：
Rongo C
中科院分区：
文献类型：
--
作者：
Kramer LB;Shim J;Previtera ML;Isack NR;Lee MC;Firestein BL;Rongo C
ampa型谷氨酸受体（AMPAR）膜运输的调节是神经元调节突触强度和可塑性的关键机制。AMPAR转运是通过受体磷酸化、泛素化、内吞作用和再循环的组合来调节的，然而介导这些过程的因素才刚刚开始被发现。在这里，我们确定了泛素偶联酶变体UEV-1作为体内AMPAR运输的调节剂。我们在秀丽隐杆线虫中间神经元AMPAR亚基GLR-1转运突变的基因筛选中发现了uev-1突变。uev-1活性的丧失导致GLR-1在神经元细胞体和沿腹脊髓神经突的细长增生中积累。突变体也有相应的行为缺陷——运动中自发逆转的减少——与GLR-1功能的减弱相一致。其他突触蛋白在uv -1突变中间神经元中的定位似乎正常，这表明GLR-1转运缺陷不是由于突触形成或整体蛋白质转运的严重缺陷。我们提供的证据表明，在uev-1突变体中，GLR-1在含有rab -10的核内体中积累，并且受体独立于网格蛋白介导的内吞作用到达这些核内体。其他物种的UEV-1同源物与泛素结合酶Ubc13结合，在底物蛋白上形成k63连接的多泛素链。我们发现，尽管UEV-1可以与秀丽隐杆线虫UBC-13相互作用，但在UEV-1突变体中，线虫中k63连锁泛素化的整体水平似乎不受影响，尽管UEV-1在大多数组织中广泛表达。然而，ubc-13突变体在表型上与uv -1突变体相似，这表明这两种蛋白确实共同调节GLR-1的运输。我们的研究结果表明，UEV-1可以调节线虫中k63相关的泛素化事件的一小部分，其中至少有一个在调节GLR-1运输中至关重要。
The regulation of AMPA-type glutamate receptor (AMPAR) membrane trafficking is a key mechanism by which neurons regulate synaptic strength and plasticity. AMPAR trafficking is modulated through a combination of receptor phosphorylation, ubiquitination, endocytosis, and recycling, yet the factors that mediate these processes are just beginning to be uncovered. Here we identify the ubiquitin-conjugating enzyme variant UEV-1 as a regulator of AMPAR trafficking in vivo. We identified mutations in uev-1 in a genetic screen for mutants with altered trafficking of the AMPAR subunit GLR-1 in C. elegans interneurons. Loss of uev-1 activity results in the accumulation of GLR-1 in elongated accretions in neuron cell bodies and along the ventral cord neurites. Mutants also have a corresponding behavioral defect—a decrease in spontaneous reversals in locomotion—consistent with diminished GLR-1 function. The localization of other synaptic proteins in uev-1-mutant interneurons appears normal, indicating that the GLR-1 trafficking defects are not due to gross deficiencies in synapse formation or overall protein trafficking. We provide evidence that GLR-1 accumulates at RAB-10-containing endosomes in uev-1 mutants, and that receptors arrive at these endosomes independent of clathrin-mediated endocytosis. UEV-1 homologs in other species bind to the ubiquitin-conjugating enzyme Ubc13 to create K63-linked polyubiquitin chains on substrate proteins. We find that whereas UEV-1 can interact with C. elegans UBC-13, global levels of K63-linked ubiquitination throughout nematodes appear to be unaffected in uev-1 mutants, even though UEV-1 is broadly expressed in most tissues. Nevertheless, ubc-13 mutants are similar in phenotype to uev-1 mutants, suggesting that the two proteins do work together to regulate GLR-1 trafficking. Our results suggest that UEV-1 could regulate a small subset of K63-linked ubiquitination events in nematodes, at least one of which is critical in regulating GLR-1 trafficking.
登录
查看更多内容
影响因子：
3.3
作者：
Chun, Denise K.;McEwen, Jason M.;Kaplan, Joshua M.
通讯作者：
Kaplan, Joshua M.
影响因子：
2.7
作者：
Collins, Tony J.
通讯作者：
Collins, Tony J.
影响因子：
16.2
作者：
Ehlers, MD
通讯作者：
Ehlers, MD
影响因子：
3.3
作者：
Glodowski, Doreen R.;Chen, Carlos Chih-Hsiung;Rongo, Christopher
通讯作者：
Rongo, Christopher
影响因子：
3.3
作者：
Firestein, BL;Rongo, C
通讯作者：
Rongo, C