期刊
JOURNAL OF CELLULAR BIOCHEMISTRY
卷 85, 期 1, 页码 131-145出版社
WILEY
DOI: 10.1002/jcb.10100
关键词
phosphatidylinositol 4-phosphate 5-kinase; phosphatidylinositol 4,5-bisphosphate; endocytosis; vesicles; PIP5K; PII domain; membrane trafficking
资金
- NCI NIH HHS [CA58291] Funding Source: Medline
- NATIONAL CANCER INSTITUTE [R29CA058291] Funding Source: NIH RePORTER
The type I phosphatidylinositol 4-phosphate 5-kinases (P14P5K) phosphorylate phosphatidylinositol 4-phosphate [PI(4)P] to produce phosphatidylinositol 4,5-bisphosphate [PI(4,5)P-2]. PI(4,5)P-2 has been implicated in signal transduction, receptor mediated endocytosis, vesicle trafficking, cytoskeletal structure, and membrane ruffling. However, the specific type I enzymes associated with the production of PI(4,5)P-2 for the specific cellular processes have not been rigorously defined. Murine P14P5K type Ibeta (mPIP5K-Ibeta) was implicated in receptor mediated endocytosis through the isolation of a truncated and inactive form of the enzyme that blocked the ligand-dependent downregulation of the colony-stimulating factor-1 receptor. The present study shows that enforced expression of mPIP5K-Ibeta in 293T cells resulted in the accumulation of large vesicles that were linked to an endosomal pathway. Similar results were obtained after the expression of the PI(4,5)P-2-binding pleckstrin homology (PH) domain of phospholipase-Cdelta (PLC-delta). Analysis of the conserved domains of mPIP5K-Ibeta led to the identification of dimerization domains in the N- and C-terminal regions. Enforced expression of the individual dimerization domains interfered with the proper subcellular localization of mPIP5K-Ibeta and the PLC-delta-PH domain and blocked the accumulation of the endocytic vesicles induced by these proteins. in addition to regulating early steps in endocytosis, these results suggest that mPIP5K-Ibeta acts through PI(4,5)P-2 to regulate endosomal trafficking and/or fusion. (C) 2002 Wiley-Liss, Inc.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据