Schmidle T, Weiler R, Desnos C, Scherman D, Fischer-Colbrie R, Floor E, Winkler H
Department of Pharmacology, University of Innsbruck, Austria.
Biochim Biophys Acta. 1991 Nov 7;1060(3):251-6. doi: 10.1016/s0005-2728(05)80314-7.
The subcellular distribution of three proteins of synaptic vesicles (synaptin/synaptophysin, p65 and SV2) was determined in bovine adrenal medulla and sympathetic nerve axons. In adrenals most p65 and SV2 is confined to chromaffin granules. Part of synaptin/synaptophysin is apparently also present in these organelles, but a considerable portion is found in a light vesicle which does not contain significant concentrations of typical markers of chromaffin granules (cytochrome b-561, dopamine beta-hydroxylase or the amine carrier). An analogous finding was obtained for sympathetic axons. The large dense core vesicles contain most p65 and also SV2 but only a smaller portion of synaptin/synaptophysin. A lighter vesicle containing this latter antigen and some SV2 has also been found. These results establish that in adrenal medulla and sympathetic axons three typical antigens of synaptic vesicles are not restricted to light vesicles. Apparently, a varying part of these antigens is found in chromaffin granules and large dense core vesicles. On the other hand, the light vesicles do not contain significant concentrations of functional antigens of chromaffin granules. Thus, the biogenesis of small presynaptic vesicles which contain all three antigens as well as functional components like the amine carrier is likely to involve considerable membrane sorting.
在牛肾上腺髓质和交感神经轴突中，测定了三种突触小泡蛋白（突触素/突触囊泡蛋白、p65和SV2）的亚细胞分布。在肾上腺中，大多数p65和SV2局限于嗜铬颗粒。突触素/突触囊泡蛋白的一部分显然也存在于这些细胞器中，但相当一部分存在于一种轻小泡中，这种轻小泡不含嗜铬颗粒典型标志物（细胞色素b-561、多巴胺β-羟化酶或胺载体）的显著浓度。在交感神经轴突中也获得了类似的发现。大的致密核心囊泡含有大多数p65和SV2，但只含有较小部分的突触素/突触囊泡蛋白。还发现了一种含有后一种抗原和一些SV2的较轻小泡。这些结果表明，在肾上腺髓质和交感神经轴突中，三种典型的突触小泡抗原并不局限于轻小泡。显然，这些抗原的不同部分存在于嗜铬颗粒和大的致密核心囊泡中。另一方面，轻小泡不含嗜铬颗粒功能性抗原的显著浓度。因此，包含所有三种抗原以及胺载体等功能成分的小突触前囊泡的生物发生可能涉及相当多的膜分选。
