Tolias K F, Cantley L C
Beth Israel Deaconess Medical Center, Harvard Institutes of Medicine, Boston, MA 02215, USA.
Chem Phys Lipids. 1999 Apr;98(1-2):69-77. doi: 10.1016/s0009-3084(99)00019-5.
In eukaryotic cells, phosphatidylinositol can be phosphorylated on the inositol ring by a series of kinases to produce at least seven distinct phosphoinositides. These lipids have been implicated in a variety of cellular processes, including calcium regulation, actin rearrangement, vesicle trafficking, cell survival and mitogenesis. The phosphorylated lipids can act as precursors of second messengers or act directly to recruit specific signaling proteins to the membrane. A number of the kinases responsible for producing these lipids have been purified and their cDNA clones have been isolated. The most well characterized of these enzymes are the phosphoinositide 3-kinases. However, progress has also been made in the characterization of phosphatidylinositol 4-kinases and phosphatidylinositol-4-phosphate 5-kinases. In addition, new pathways involving phosphatidylinositol-5-phosphate 4-kinases, phosphatidylinositol-3-phosphate 5-kinases and phosphatidylinositol-3-phosphate 4-kinases have recently been described. The various enzymes and pathways involved in the synthesis of cellular phosphoinositides will be discussed.
在真核细胞中，磷脂酰肌醇可通过一系列激酶在肌醇环上磷酸化，产生至少七种不同的磷酸肌醇。这些脂质参与了多种细胞过程，包括钙调节、肌动蛋白重排、囊泡运输、细胞存活和有丝分裂。磷酸化脂质可作为第二信使的前体，或直接作用于招募特定的信号蛋白至细胞膜。许多负责产生这些脂质的激酶已被纯化，其cDNA克隆也已分离。其中最具特征的酶是磷酸肌醇3激酶。然而，在磷脂酰肌醇4激酶和磷脂酰肌醇-4-磷酸5激酶的表征方面也取得了进展。此外，最近还描述了涉及磷脂酰肌醇-5-磷酸4激酶、磷脂酰肌醇-3-磷酸5激酶和磷脂酰肌醇-3-磷酸4激酶的新途径。本文将讨论参与细胞磷酸肌醇合成的各种酶和途径。
