Illinger D, Kuhry J G
Laboratoire de Biophysique, URA491 du Centre National de la Recherche Scientifique, Université Louis Pasteur, Strasbourg, France.
J Cell Biol. 1994 May;125(4):783-94. doi: 10.1083/jcb.125.4.783.
TMA-DPH (1-(4-trimethylammonium)-6-phenyl-1,3,5-hexatriene), a hydrophobic fluorescent membrane probe, interacts with living cells by instantaneous incorporation into the plasma membrane, where it becomes fluorescent. It then follows the intracellular constitutive membrane traffic and acts as a bulk membrane marker of the endocytic pathway (Illinger, D., P. Poindron, P. Fonteneau, M. Modolell, and J. G. Kuhry. 1990. Biochim. Biophys. Acta. 1030:73-81; Illinger, D., P. Poindron, and J. G. Kuhry. 1991. Biol. Cell. 73:131-138). As such, TMA-DPH displays particular properties mainly due to partition between membranes and aqueous media. From these properties, original arguments can be inferred in favor of the maturation model for the endocytic pathway, against that of pre-existing compartments, in L929 cultured mouse fibroblasts. (a) TMA-DPH labeling is seen to progress from the cell periphery to perinuclear regions during endocytosis without any noticeable loss in fluorescence intensity; with a vesicle shuttle model this evolution would be accompanied by probe dilution with a decrease in the overall intracellular fluorescence intensity, and the labeling of the inner (late) compartments could in no way become more intense than that of the peripheral (early) ones. (b) From TMA-DPH fluorescence anisotropy assays, it is concluded that membrane fluidity is the same in the successive endocytic compartments as in the plasma membrane, which probably denotes a similar phospholipidic membrane composition, as might be expected in the maturation model. (c) TMA-DPH internalization and release kinetics are more easily described with the maturation model.
TMA-DPH（1-（4-三甲基铵）-6-苯基-1,3,5-己三烯）是一种疏水性荧光膜探针，通过瞬间掺入质膜与活细胞相互作用，在质膜中它会发出荧光。然后它追踪细胞内组成型膜运输，并作为内吞途径的整体膜标记物（伊林格，D.，P. 普安德龙，P. 丰特诺，M. 莫多雷尔，和 J. G. 库里。1990.《生物化学与生物物理学报》。1030:73 - 81；伊林格，D.，P. 普安德龙，和 J. G. 库里。1991.《生物细胞》。73:131 - 138）。因此，TMA-DPH 表现出特殊性质，主要归因于其在膜和水相介质之间的分配。基于这些性质，可以推断出支持 L929 培养的小鼠成纤维细胞内吞途径成熟模型的原始论据，以反对预先存在区室的模型。（a）在内吞过程中，可见 TMA-DPH 标记从细胞周边向核周区域发展，荧光强度没有任何明显损失；在囊泡穿梭模型中，这种演变会伴随着探针稀释，导致细胞内整体荧光强度降低，并且内部（晚期）区室的标记绝不可能比周边（早期）区室的标记更强烈。（b）从 TMA-DPH 荧光各向异性测定得出结论，连续内吞区室中的膜流动性与质膜中的相同，这可能表明磷脂膜组成相似，这在成熟模型中是可以预期的。（c）用成熟模型更容易描述 TMA-DPH 的内化和释放动力学。
