Figure 1

Schematic representation of the effects of depleting TANGO (transport and Golgi organization) genes on Golgi organization. (a) The constitutive protein secretory pathway in Drosophila S2 cells, showing its major compartments. The red arrow indicates the route through which the reporter signal sequence-HRP protein (ss-HRP) used in the RNAi screen by Bard et al. [12] is transported and secreted. The Golgi membranes marked by mannosidase II (ManII)-GFP are outlined in green. The lumen of the endoplasmic reticulum (ER) is shaded pale gray. tER, transitional endoplasmic reticulum; PM, plasma membrane. (b) The four phenotypes (classes A-D) that Bard et al. [12] identified as a result of the depletion of 130 TANGO genes are shown here; they were defined by the localization of ManII-GFP, which normally resides in the Golgi stacks. Depletion of class A genes led to a redistribution of ManII-GFP to the endoplasmic reticulum; depletion of class B genes caused fragmentation of Golgi membranes; knock-down of class C genes led to aggregation of ManII-GFP-positive membranes (and formation of ring-like structures); and depletion of class D genes inhibited protein secretion but did not affect the Golgi structure. The 20 TANGO proteins that were further characterized by Bard et al. [12] are listed under the diagram depicting the phenotype induced by their depletion. Proteins containing at least one putative transmembrane domain are marked with an asterisk.