Independent yet overlapping pathways ensure the robustness and responsiveness of trans-Golgi network functions in Arabidopsis

Citations Over TimeTop 15% of 2018 papers

Abstract

The trans-Golgi-network (TGN) has essential housekeeping functions in secretion, endocytosis and protein sorting, but also more specialized functions in plant development. How the robustness of basal TGN function is ensured while specialized functions are differentially regulated is poorly understood. Here, we investigate two key regulators of TGN structure and function, ECHIDNA and the Transport Protein Particle II (TRAPPII) tethering complex. An analysis of physical, network and genetic interactions suggests that two network communities are implicated in TGN function and that ECHIDNA and TRAPPII belong to distinct yet overlapping pathways. Whereas ECHIDNA and TRAPPII colocalized at the TGN in interphase cells, their localization diverged in dividing cells. Moreover, ECHIDNA and TRAPPII localization patterns were mutually independent. TGN structure, endocytosis and sorting decisions were differentially impacted in echidna and trappii mutants. Our analyses point to a partitioning of specialized TGN functions, with ECHIDNA being required for cell elongation and TRAPPII for cytokinesis. Two independent pathways able to compensate for each other might contribute to the robustness of TGN housekeeping functions and to the responsiveness and fine tuning of its specialized functions.

Related Papers

• → Salinity tolerance of Arabidopsis: a good model for cereals?(2007)129 cited
• Expression of a rice OsARGOS gene in Arabidopsis promotes cell division and expansion and increases organ size(2009)
• → Ultrastructural Distribution of NADPase within the Golgi Apparatus and Lysosomes of Mammalian Cells(1990)18 cited
• → An Arabidopsis ETR1 Homologue is Constituvely Expressed in Peach Fruit Abscission Zone and Mesocarp(1999)3 cited
• HsfAld, a Protein Identified via FOX Hunting Using Thellungiella salsuginea cDNAs Improves Heat Tolerance by Regulating Heat-Stress-Responsive Gene Expression(2013)