Melin P M, Sommarin M, Sandelius A S, Jergil B
Department of Biochemistry, Chemical Centre, Lund, Sweden.
FEBS Lett. 1987 Oct 19;223(1):87-91. doi: 10.1016/0014-5793(87)80515-x.
A polyphosphoinositide phospholipase C has been identified in highly purified plasma membranes from shoots and roots of wheat seedlings. The enzyme preferentially hydrolysed phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate and had a different phosphoinositide substrate profile from soluble phospholipase C. The enzyme activity was lower in plasma membranes isolated from light-grown shoots than from dark-grown ones, whereas no differences in activity between plasma membranes from light- and dark-grown roots were seen. Maximum activity of the membrane-bound enzyme was observed around pH 6. It was activated by micromolar concentrations of Ca2+, but not by GTP or GTP analogues. The enzyme may participate in signal transduction over the plant plasma membrane.
在从小麦幼苗的芽和根中高度纯化的质膜中已鉴定出一种多磷酸肌醇磷脂酶C。该酶优先水解磷脂酰肌醇4-磷酸和磷脂酰肌醇4,5-二磷酸，并且与可溶性磷脂酶C具有不同的磷酸肌醇底物谱。从光照下生长的芽中分离出的质膜中的酶活性低于从黑暗中生长的芽中分离出的质膜，而在光照和黑暗中生长的根的质膜之间未观察到活性差异。膜结合酶的最大活性在pH 6左右观察到。它被微摩尔浓度的Ca2+激活，但不被GTP或GTP类似物激活。该酶可能参与植物质膜上的信号转导。
