Kölling Ralf
Institut für Mikrobiologie, Geb. 26.12.01, Heinrich-Heine-Universität Düsseldorf, 40225, Düsseldorf, Germany.
FEBS Lett. 2002 Nov 20;531(3):548-52. doi: 10.1016/s0014-5793(02)03621-9.
In this report, the role of phosphorylation in the regulation of ubiquitination and turnover of the ABC-transporter Ste6 was investigated. We demonstrate that Ste6 is phosphorylated in vivo and that this phosphorylation is dependent on the presence of an acidic stretch ('A-box') in the linker region previously shown to be important for ubiquitination and fast turnover of Ste6. By mutagenesis, two serine/threonine residues were identified in the A-box region that are crucial for ubiquitination and trafficking to the yeast vacuole. In the mutants there was no simple correlation between phosphorylation and ubiquitination levels, suggesting that the two events may not be coupled.
在本报告中，研究了磷酸化在ABC转运蛋白Ste6的泛素化调控及周转中的作用。我们证明，Ste6在体内会发生磷酸化，且这种磷酸化依赖于连接区中一个酸性序列（“A盒”）的存在，此前已表明该区域对Ste6的泛素化和快速周转很重要。通过诱变，在A盒区域鉴定出两个丝氨酸/苏氨酸残基，它们对泛素化及转运至酵母液泡至关重要。在这些突变体中，磷酸化水平与泛素化水平之间没有简单的相关性，这表明这两个事件可能没有关联。
