The kinesin-like motor protein KIF1C occurs in intact cells as a dimer and associates with proteins of the 14-3-3 family
The kinesin-like motor protein KIF1C occurs in intact cells as a dimer and associates with proteins of the 14-3-3 family
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DOI：
10.1074/jbc.274.47.33654
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发表时间：
1999-11-19
影响因子：
4.8
通讯作者：
Lammers, R
中科院分区：
文献类型：
--
作者：
Dorner, C;Ullrich, A;Lammers, R
运动蛋白超家族的蛋白质通过羧基末端相关蛋白和磷酸化调节其运动活性以及与货物结合的能力。KIF1C是最近发现的KIF1/Unc104家族成员，被证明参与从高尔基体到内质网的逆行囊泡运输。在使用KIF1C的羧基末端350个氨基酸作为诱饵的酵母双杂交筛选中，我们鉴定出了结合蛋白14-3-3 β， γ， epsilon和zeta。此外，还发现了一个编码KIF1C羧基末端290个氨基酸的克隆，表明KIF1C具有二聚化的潜力。随后的瞬时过表达实验表明，KIF1C可以有效地二聚体化。然而，在未转染的细胞中，只有一小部分KIF1C被检测为二聚体。14-3-3蛋白与KIF1C的关联可以在瞬时表达系统和未转染的细胞中得到证实，并且依赖于位于14-3-3配体一致结合序列上的丝氨酸1092的磷酸化。丝氨酸1092是蛋白激酶酪蛋白激酶II的底物，酪蛋白激酶II在细胞中的抑制降低了KIF1C与14-3-3 γ的关联。因此，我们的数据表明KIF1C可以形成二聚体，并与14-3-3家族的蛋白质相关。
Proteins of the kinesin superfamily are regulated in their motor activity as well as in their ability to bind to their cargo by carboxyl-terminal associating proteins and phosphorylation. KIF1C, a recently identified member of the KIF1/Unc104 family, was shown to be involved in the retrograde vesicle transport from the Golgi-apparatus to the endoplasmic reticulum. In a yeast two-hybrid screen using the carboxyl-terminal 350 amino acids of KIF1C as a bait, we identified as binding proteins 14-3-3 beta, gamma, epsilon, and zeta. In addition, a clone encoding the carboxyl-terminal 290 amino acids of KIF1C was found, indicating a potential for KIF1C to dimerize. Subsequent transient overexpression experiments showed that KIF1C can dimerize efficiently. However, in untransfected cells, only a small portion of KIF1C was detected as a dimer. The association of 14-3-3 proteins with KIF1C could be confirmed in transient expression systems and in untransfected cells and was dependent on the phosphorylation of serine 1092 located in a consensus binding sequence for 14-3-3 ligands. Serine 1092 was a substrate for the protein kinase casein kinase II in vitro, and inhibition of casein kinase II in cells diminished the association of KIF1C with 14-3-3 gamma. Our data thus suggest that KIF1C can form dimers and is associated with proteins of the 14-3-3 family.