Vesicle Transport in Plants: A Revised Phylogeny of SNARE Proteins.

Xiaoyan Gu,Keith Lindsey,Guangqin Guo,Adrian Brennan,Wenbin Wei

doi:10.1177/1176934320956575

Abstract

Communication systems within and between plant cells involve the transfer of ions and molecules between compartments, and are essential for development and responses to biotic and abiotic stresses. This in turn requires the regulated movement and fusion of membrane systems with their associated cargo. Recent advances in genomics has provided new resources with which to investigate the evolutionary relationships between membrane proteins across plant species. Members of the soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are known to play important roles in vesicle trafficking across plant, animal and microbial species. Using recent public expression and transcriptomic data from 9 representative green plants, we investigated the evolution of the SNARE classes and linked protein changes to functional specialization (expression patterns). We identified an additional 3 putative SNARE genes in the model plant Arabidopsis. We found that all SNARE classes have expanded in number to a greater or lesser degree alongside the evolution of multicellularity, and that within-species expansions are also common. These gene expansions appear to be associated with the accumulation of amino acid changes and with sub-functionalization of SNARE family members to different tissues. These results provide an insight into SNARE protein evolution and functional specialization. The work provides a platform for hypothesis-building and future research into the precise functions of these proteins in plant development and responses to the environment.

Highlights

Communication between cells, and between compartments within cells, depends on membrane structure and function, and is fundamental to plant and animal growth and development and responses to environmental stresses
A search of PANTHER homologues of Arabidopsis sensitive factor attachment protein receptors (SNAREs) genes led to the identification of 3 new putative Arabidopsis SNARE homologues; 2 Qc-SNARE homologues, AT1G16225 and AT1G16230; and an R-SNARE homologue, AT3G25013, and many other similar genes across the 8 other target species
For the Qa-SNAREs, we identified 8 distinct clades that are highly conserved across plants (Figure 2)

Summary

Introduction

Communication between cells, and between compartments within cells, depends on membrane structure and function, and is fundamental to plant and animal growth and development and responses to environmental stresses. Coat proteins and dynaminrelated GTPases in a donor compartment are used to form a vesicle and deform the local membrane until a vesicle is freed by scission. Molecular motors including kinesin and myosin have all been shown to be involved in this process.[2,3] tethering and docking factors work in conjunction with Rab GTPases and SNARE proteins to tether the vesicle to their acceptor membrane.[4] In the final, fusion step, a tetrameric target (t)-SNARE complex is formed from a single v-SNARE molecule (members of the synaptobrevin or VAMP family of proteins) and a trimeric target membrane t-SNARE complex (members of the syntaxin and SNAP-25 families) that allows vesicles to identify their target compartment and complete membrane fusion and cargo delivery.[5,6,7,8,9]

Methods

Results

Discussion

Conclusion