Genome-Wide Identification of the Invertase Gene Family in Populus.

Zhong Chen,Xinmin An,Xiaoxing Su,Pian Rao,Kai Gao,Changjie Xu

doi:10.1371/journal.pone.0138540

Zhong Chen, Xinmin An + Show 4 more

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https://doi.org/10.1371/journal.pone.0138540

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Journal: PloS one	Publication Date: Sep 22, 2015
Citations: 49	License type: CC BY 4.0

Affiliation: Beijing Forestry University, Berry Oncology (China)

Abstract

Invertase plays a crucial role in carbohydrate partitioning and plant development as it catalyses the irreversible hydrolysis of sucrose into glucose and fructose. The invertase family in plants is composed of two sub-families: acid invertases, which are targeted to the cell wall and vacuole; and neutral/alkaline invertases, which function in the cytosol. In this study, 5 cell wall invertase genes (PtCWINV1-5), 3 vacuolar invertase genes (PtVINV1-3) and 16 neutral/alkaline invertase genes (PtNINV1-16) were identified in the Populus genome and found to be distributed on 14 chromosomes. A comprehensive analysis of poplar invertase genes was performed, including structures, chromosome location, phylogeny, evolutionary pattern and expression profiles. Phylogenetic analysis indicated that the two sub-families were both divided into two clades. Segmental duplication is contributed to neutral/alkaline sub-family expansion. Furthermore, the Populus invertase genes displayed differential expression in roots, stems, leaves, leaf buds and in response to salt/cold stress and pathogen infection. In addition, the analysis of enzyme activity and sugar content revealed that invertase genes play key roles in the sucrose metabolism of various tissues and organs in poplar. This work lays the foundation for future functional analysis of the invertase genes in Populus and other woody perennials.

Highlights

In higher plants, carbon autotrophy is a prominent feature and sucrose is the major form of transported sugar [1]
After manual reannotation and confirmation of the protein characteristic domain, the 24 Populus invertase genes were designated PtrCWINV1-5, PtrVINV1-3, and PtrNINV1-16 following the nomenclature proposed in a previous study [6]
Phylogenetic analysis revealed that the acid invertase sub-family could be separated into α and β clades (Fig 3)

Summary

Introduction

Carbon autotrophy is a prominent feature and sucrose is the major form of transported sugar [1]. Sucrose is synthesised in source leaves and translocated to non-photosynthetic sink tissues. This disaccharide and its cleavage products, glucose and fructose, play central roles in cell metabolism and plant growth and development [2]. Sucrose utilisation as a source of carbon and energy depends on its hydrolysis into hexoses; in plants this reaction is catalysed by enzymes: sucrose synthase (EC 2.4.1.13) and invertase (EC 3.2.1.26). Sucrose synthase catalyses the readily reversible hydrolysis of sucrose into UDP-glucose and fructose, whereas invertase is responsible for the irreversible cleavage of sucrose to glucose and fructose [3].

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