Towards understanding of plant mitochondrial VDAC proteins: an overview of bean (&lt;em&gt;Phaseolus&lt;/em&gt;) VDAC proteins

Hayet Saidani,Marc Léonetti,Daria Grobys,Hanna Kmita,Fabrice Homblé

doi:10.3934/biophy.2017.1.43

Abstract

As the main grain legume consumed worldwide, the common bean (Phaseolus vulgaris) is generally considered as a model for food legumes. The mitochondrial voltage-dependent anion-selective channel (VDAC) is the major transport pathway for inorganic ions, metabolites, and tRNA, and consequently it controls the exchange of these compounds between the cytoplasm and the mitochondrion. Two VDAC isoforms of Phaseolus coccineus have been investigated experimentally. However, plant VDACs are known to belong to a small multigenic family of variable size. Here, we combine available experimental as well as genomic and transcriptomic data to identify and characterize the VDAC family of Phaseolus vulgaris. To this aim, we review the current state of our knowledge of Phaseolus VDAC functional and structural properties. The genomic and transcriptomic data available for the putative VDACs of Phaseolus vulgaris are studied using bioinformatics approach including homology modelling. The obtained results indicate that five out of the seven putative VDAC encoding sequences (named PvVDAC1–5) share strongly conserved motifs and structural homology with known VDACs. Notably, PvVDAC4 and PvVDAC5 are very close to the two abundant and characterized experimentally VDAC isoforms purified from Phaseolus coccineus mitochondria.

Highlights

A big societal challenge is to increase the yields of crop plants without detrimental impact on the environment
Our current knowledge of structure-function relationships in the case of plant voltage-dependent anionselective channel (VDAC) proteins is mainly based on data obtained for PcVDAC32 from P. coccineus
Two PcVDAC isoforms are known to be expressed in P. coccineus seeds, little is known about the number of plant VDAC isoforms and their role in plant cell physiology

Summary

Introduction

A big societal challenge is to increase the yields of crop plants without detrimental impact on the environment. The voltage-dependent anion-selective channel (VDAC) is the major pathway for metabolite (e.g., ATP) and ion transport through MOM As such, it may have central role in the regulation of mitochondrial and cell metabolism and thereby in the seed development and germination. As VDAC plays a central role at the cytoplasm-mitochondrial interface, it is of prime importance to identify its various isoforms that are expressed in different plants, to study their expression, to decipher their structure-function relationship and to understand regulating mechanisms. In this framework, we provide here the current state of our knowledge of Phaseolus VDAC functional and structural properties hoping that it will pave the way for future research

Functional Features

Structural Features

Phaseolus VDAC Isoforms

Findings

Conclusions