Dataset Information

Interactions between Transport Protein Particle (TRAPP) complexes and Rab GTPases in Arabidopsis

ABSTRACT: The Transport Protein Particle II (TRAPPII) is essential for exocytosis, endocytosis, protein sorting and cytokinesis. In spite of a considerable understanding of its biological role, little is known about Arabidopsis TRAPPII complex topology and molecular function. In this study, independent proteomic approaches initiated with TRAPP components or Rab-A GTPase variants converge on the TRAPPII complex. We show that the Arabidopsis genome encodes the full complement of 13 TRAPPC subunits, including four previously unidentified components. A dimerization model is proposed to account for binary interactions between TRAPPII subunits. Preferential binding to dominant negative (GDP-bound) versus wild-type or constitutively active (GTP-bound) RAB-A2a variants discriminates between TRAPPII and TRAPPIII subunits and shows that Arabidopsis complexes differ from yeast but resemble metazoan TRAPP complexes. While the TRAPPII complex has been implicated in biosynthetic pathways, TRAPPIII appears to be implicated in degradative pathways. Analyses of Rab-A variants in trappii backgrounds provide genetic evidence for the conclusion that the TRAPPII complex behaves as a Guanine-nucleotide Exchange Factor (GEF) for the RAB-A2a GTPase. GEFs catalyze exchange of GDP for GTP; the GTP-bound, activated, Rab then recruits a diverse local network of Rab effectors to specify membrane identity in subsequent vesicle fusion events. Understanding the control of GEF-Rab interactions will be crucial to unraveling the co-ordination of membrane traffic.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)

TISSUE(S): Flower, Root

SUBMITTER: Christina Ludwig

LAB HEAD: Christina Ludwig

PROVIDER: PXD013016 | Pride | 2019-09-03

REPOSITORIES: Pride

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			Action	DRS
	00708_A01_P005278_B00_A00_R1.raw	Raw
	00752_A01_P005882_B00_A00_R1.raw	Raw
	00752_B01_P005883_B00_A00_R1.raw	Raw
	00752_D01_P005885_B00_A00_R1.raw	Raw
	00752_E01_P005886_B00_A00_R1.raw	Raw

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Interactions between Transport Protein Particle (TRAPP) complexes and Rab GTPases in Arabidopsis.

Kalde Monika M Elliott Liam L Ravikumar Raksha R Rybak Katarzyna K Altmann Melina M Klaeger Susan S Wiese Christian C Abele Miriam M Al Benjamin B Kalbfuß Nils N Qi Xingyun X Steiner Alexander A Meng Chen C Zheng Huanquan H Kuster Bernhard B Falter-Braun Pascal P Ludwig Christina C Moore Ian I Assaad Farhah F FF

The Plant journal : for cell and molecular biology 20190805 2

Transport Protein Particle II (TRAPPII) is essential for exocytosis, endocytosis, protein sorting and cytokinesis. In spite of a considerable understanding of its biological role, little information is known about Arabidopsis TRAPPII complex topology and molecular function. In this study, independent proteomic approaches initiated with TRAPP components or Rab-A GTPase variants converge on the TRAPPII complex. We show that the Arabidopsis genome encodes the full complement of 13 TRAPPC subunits, ...[more]

PMID: 31264742

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