A comparative study of the activation of protein kinase C α by different diacylglycerol isomers
A comparative study of the activation of protein kinase C α by different diacylglycerol isomers
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DOI：
10.1042/0264-6021:3370387
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发表时间：
1999-02-01
影响因子：
4.1
通讯作者：
Gómez-Fernández, JC
中科院分区：
文献类型：
--
作者：
Sánchez-Piñera, P;Micol, V;Gómez-Fernández, JC
通过比较不同的1，2-二酰基甘油和1，3-二酰基甘油掺入混合胶束或囊泡中的活化能力，研究了蛋白激酶C α（PKC α）的脂质活化。当使用1-棕榈酰-2-油酰-sn-甘油-3-磷酸丝氨酸（POPS）/Triton X-100混合胶束和纯POPS囊泡时，不饱和的1，2-二酰基甘油一般比饱和的1，2-二酰基甘油具有更强的激活作用。相反，当使用1-棕榈酰-2-油酰-sn-甘油-3-磷酸胆碱（POPC）/POPS（4.1，摩尔比）囊泡时，未观察到这些差异。具有短脂肪酰基链的甘油二酯表现出非常高的活化能力，然而，在混合胶束中的能力较小。此外，1，2-二酰基甘油在POPS/Triton X-100混合胶束和POPC/POPS囊泡中的活化能力显著高于1，3-二酰基甘油。然而，当使用纯的POPS囊泡时，两种类型的二酰基甘油之间的差异较小。差示扫描量热法（DSC）表明，POPC/POPS膜样品含有二酰基甘油在200 μ M的Ca 2+和5 mM的Mg 2+的存在下有吸热转变。当使用纯POPS囊泡时，由于形成脱水相，如FTIR（傅里叶变换红外）光谱所示，未检测到过渡。在200 μ M Ca 2+和5 mM Mg 2+存在下通过差速离心进行的PKC α结合研究表明，1，2-sn-二油酰甘油（1，2-DOG）在促进与POPC/POPS囊泡的结合方面比1，3-二油酰甘油（1，3-DOG）更有效。然而，当使用纯的POPS囊泡时，PKC α能够以相同的程度与含有1，2-DOG或1，3-DOG的膜结合。
The lipid activation of protein kinase C alpha (PKC alpha) has been studied by comparing the activation capacity of different 1,2-diacylglycerols and 1,3-diacylglycerols incorporated into mixed micelles or vesicles. Unsaturated 1,2-diacylglycerols were, in general, more potent activators than saturated ones when 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoserine (POPS)/Triton X-100 mixed micelles and pure POPS vesicles were used. In contrast, these differences were not observed when 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/POPS (4.1, molar ratio) vesicles were used. Diacylglycerols bearing short fatty acyl chains showed a very high activation capacity, however, the capacity was less in mixed micelles. Furthermore, 1,2-diacylglycerols had a considerably higher activating capacity than 1,3-diacylglycerols in POPS/Triton X-100 mixed micelles and in POPC/POPS vesicles. However, the differences between the two types of diacylglycerols were smaller when pure POPS vesicles were used. Differential scanning calorimetry (DSC) showed that POPC/POPS membrane samples containing diacylglycerols had endothermic transitions in the presence of 200 mu M Ca2+ and 5 mM Mg2+. Transitions were not detected when using pure POPS vesicles due to the formation of dehydrated phases as demonstrated by FTIR (Fourier-transform infrared) spectroscopy. PKC alpha binding studies, performed by differential centrifugation in the presence of 200 mu M Ca2+ and 5 mM Mg2+, showed that 1,2-sn-dioleoylglycerol (1,2-DOG) was more effective than 1,3-dioleoylglycerol (1,3-DOG) in promoting binding to POPC/POPS vesicles. However, when pure POPS vesicles were used, PKC alpha was able to bind to membranes containing either 1,2-DOG or 1,3-DOG to the same extent.