Istituto di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, Milano, Italy.
Traffic. 2013 Jun;14(6):622-8. doi: 10.1111/tra.12051. Epub 2013 Feb 25.
Tonoplast, the membrane delimiting plant vacuoles, regulates ion, water and nutrient movement between the cytosol and the vacuolar lumen through the activity of its membrane proteins. Correct traffic of proteins from the endoplasmic reticulum (ER) to the tonoplast requires (i) approval by the ER quality control, (ii) motifs for exit from the ER and (iii) motifs that promote sorting to the tonoplast. Recent evidence suggests that this traffic follows different pathways that are protein-specific and could also reflect vacuole specialization for lytic or storage function. The routes can be distinguished based on their sensitivity to drugs such as brefeldin A and C834 as well as using mutant plants that are defective in adaptor proteins of vesicle coats, or dominant-negative mutants of Rab GTPases.
液泡膜将植物液泡与细胞质隔开，通过其膜蛋白的活动调节离子、水和养分在细胞质和液泡腔之间的移动。蛋白质从内质网（ER）正确运输到液泡膜需要（i）内质网质量控制的批准，（ii）从 ER 出口的基序，以及（iii）促进分选到液泡膜的基序。最近的证据表明，这种运输遵循不同的途径，这些途径是蛋白质特异性的，也可能反映出液泡在溶酶体或储存功能方面的专门化。这些途径可以根据它们对布雷菲德菌素 A 和 C834 等药物的敏感性以及使用在囊泡外套的衔接蛋白有缺陷的突变体植物或 Rab GTPase 的显性负突变体来区分。
