Genome-Wide Identification and Characterization of Xyloglucan Endotransglycosylase/Hydrolase in Ananas comosus during Development.

Qingyun Li,Yudong Chen,Chongyang Yin,Qing Jiang,Long Yang,Rui Zhang,Huayang Li,Xiaotong Wang,Fangfang Ge

doi:10.3390/genes10070537

Abstract

Xyloglucan endotransglycosylase/hydrolase (XTH) is a cell-wall-modifying enzyme participating in diverse cell morphogenetic processes and adaptation to stress. In this study, 48 XTH genes were identified from two pineapple (Ananas comosus) cultivars (‘F153’ and ‘MD2’) and designated Ac(F153)XTH1 to -24 and Ac(MD2)XTH1 to -24 based on their orthology with Arabidopsis thaliana genes. Endoglucanase family 16 members were identified in addition to XTHs of glycoside hydrolase family 16. Phylogenetic analysis clustered the XTHs into three major groups (Group I/II, III and Ancestral Group) and Group III was subdivided into Group IIIA and Group IIIB. Similar gene structure and motif number were observed within a group. Two highly conserved domains, glycosyl hydrolase family 16 (GH16-XET) and xyloglucan endotransglycosylase C-terminus (C-XET), were detected by multiple sequences alignment of all XTHs. Segmental replication were detected in the two cultivars, with only the paralogous pair Ac(F153)XTH7-Ac(F153)XTH18 presented in ‘F153’ prior to genomic expansion. Transcriptomic analysis indicated that XTHs were involved in the regulation of fruit ripening and crassulacean acid metabolism with tissue specificity and quantitative real-time PCR analysis suggested that Ac(MD2)XTH18 was involved in root growth. The results enhance our understanding of XTHs in the plant kingdom and provide a basis for further studies of functional diversity in A. comosus.

Highlights

Pineapple (Ananas comosus), a member of the Bromeliaceae family, is cultivated widely in tropical and subtropical regions and is renowned for its nutritional and medicinal values [1]
As a vital cell-wall-modifying enzyme, Xyloglucan endotransglycosylase/hydrolase (XTH) is implicated in the incorporation or hydrolysis
As a vital cell-wall-modifying enzyme, XTH is implicated in the incorporation or hydrolysis of of XyG to regulate cell wall remodeling and degradation

Summary

Introduction

Pineapple (Ananas comosus), a member of the Bromeliaceae family, is cultivated widely in tropical and subtropical regions and is renowned for its nutritional and medicinal values [1]. Given its status as a herbaceous perennial monocotyledon with classical crassulacean acid metabolism (CAM), the pineapple genome was sequenced in 2015 as a model plant [2]. The genome of the cultivar ‘MD2’, which is the predominant pineapple cultivar grown worldwide by virtue of its fruit flesh flavor and commercial value, and the cultivar ‘F153’ has been sequenced [3]. Xyloglucan endotransglycosylase/hydrolase (XTH) participates in diverse physiological processes, especially cell elongation and stress resistance [6]. XTH is a cell-wall-modifying enzyme encoded by a multigene, which belongs to a subfamily of the glycoside hydrolase family 16 (GH16) [7,8].

Methods

Results

Conclusion