Components of a ubiquitin ligase complex specify polyubiquitination and intracellular trafficking of the general amino acid permease.
Components of a ubiquitin ligase complex specify polyubiquitination and intracellular trafficking of the general amino acid permease.
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DOI：
10.1083/jcb.153.4.649
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发表时间：
2001-05-14
期刊：
影响因子：
--
通讯作者：
Kaiser CA
中科院分区：
文献类型：
--
作者：
Helliwell SB;Losko S;Kaiser CA
Gap1p是酿酒酵母的一般氨基酸渗透酶，由发生在高尔基体或内体室的细胞内分选决定调节。根据氮源的不同，Gap1p被运送到质膜，在那里它起氨基酸摄取的作用，或者被运送到液泡，在那里它被降解。我们发现，Rsp5p e3 -泛素连接酶复合体的两个非必需组分Bul1p或Bul2p的过表达导致Gap1p被分选到液泡中，无论氮源如何。双突变体bul1Δ bul2Δ具有相反的表型，导致Gap1p比野生型细胞更有效地传递到质膜上。此外，bul1Δ bul2Δ可以逆转lst4Δ的作用，lst4Δ是一种通常阻止Gap1p到达质膜的突变。对Gap1p泛素化的评估显示，一个显著的多泛素化物种在bul1Δ bul2Δ突变体中大大减少。rsp5-1突变体和Gap1p的cooh末端截断都表现为bul1Δ bul2Δ，导致Gap1p向质膜的组成性传递，并降低Gap1p的多泛素化。这些结果表明，Bul1p和Bul2p与Rsp5p一起，在Gap1p上产生多泛素信号，指定其细胞内靶向液泡。
Gap1p, the general amino acid permease of Saccharomyces cerevisiae, is regulated by intracellular sorting decisions that occur in either Golgi or endosomal compartments. Depending on nitrogen source, Gap1p is transported to the plasma membrane, where it functions for amino acid uptake, or to the vacuole, where it is degraded. We found that overexpression of Bul1p or Bul2p, two nonessential components of the Rsp5p E3–ubiquitin ligase complex, causes Gap1p to be sorted to the vacuole regardless of nitrogen source. The double mutant bul1Δ bul2Δ has the inverse phenotype, causing Gap1p to be delivered to the plasma membrane more efficiently than in wild-type cells. In addition, bul1Δ bul2Δ can reverse the effect of lst4Δ, a mutation that normally prevents Gap1p from reaching the plasma membrane. Evaluation of Gap1p ubiquitination revealed a prominent polyubiquitinated species that was greatly diminished in a bul1Δ bul2Δ mutant. Both a rsp5-1 mutant and a COOH-terminal truncation of Gap1p behave as bul1Δ bul2Δ, causing constitutive delivery of Gap1p to the plasma membrane and decreasing Gap1p polyubiquitination. These results indicate that Bul1p and Bul2p, together with Rsp5p, generate a polyubiquitin signal on Gap1p that specifies its intracellular targeting to the vacuole.
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影响因子：
3.6
作者：
HEIN, C;SPRINGAEL, JY;ANDRE, B
通讯作者：
ANDRE, B
影响因子：
64.5
作者：
Koegl, M;Hoppe, T;Jentsch, S
通讯作者：
Jentsch, S
影响因子：
7.8
作者：
Beck, T;Schmidt, A;Hall, MN
通讯作者：
Hall, MN
在酿酒酵母中，泛素化在线粒体遗传中的作用。
影响因子：
7.8
作者：
Fisk, H A;Yaffe, M P
通讯作者：
Yaffe, M P
影响因子：
3.3
作者：
BENEDETTI, H;RATHS, S;RIEZMAN, H
通讯作者：
RIEZMAN, H