Genome-wide identification, characterization of expansin gene family of banana and their expression pattern under various stresses

Suthanthiram Backiyarani; Chelliah Anuradha; Raman Thangavelu; Arumugam Chandrasekar; Baratvaj Renganathan; Parasuraman Subeshkumar; Palaniappan Giribabu; Muthusamy Muthusamy; Subbaraya Uma

doi:10.1007/s13205-021-03106-x

Genome-wide identification, characterization of expansin gene family of banana and their expression pattern under various stresses

3 Biotech. 2022 Apr;12(4):101. doi: 10.1007/s13205-021-03106-x. Epub 2022 Mar 28.

Authors

Suthanthiram Backiyarani¹, Chelliah Anuradha¹, Raman Thangavelu¹, Arumugam Chandrasekar¹, Baratvaj Renganathan¹, Parasuraman Subeshkumar¹, Palaniappan Giribabu¹, Muthusamy Muthusamy², Subbaraya Uma¹

Affiliations

¹ ICAR-National Research Centre for Banana, Thogamalai Road, Thayanur Post, Tiruchchirappalli, Tamil Nadu 620 102 India.
² Department of Agricultural Biotechnology, National Institute of Agricultural Sciences (NAS), RDA, Jeonju, 54874 Korea.

Abstract

Expansin, a cell wall-modifying gene family, has been well characterized and its role in biotic and abiotic stress resistance has been proven in many monocots, but not yet studied in banana, a unique model crop. Banana is one of the staple food crops in developing countries and its production is highly influenced by various biotic and abiotic factors. Characterizing the expansin genes of the ancestor genome (M. acuminata and M. balbisiana) of present day cultivated banana will enlighten their role in growth and development, and stress responses. In the present study, 58 (MaEXPs) and 55 (MbaEXPs) putative expansin genes were identified in A and B genome, respectively, and were grouped in four subfamilies based on phylogenetic analysis. Gene structure and its duplications revealed that EXPA genes are highly conserved and are under negative selection whereas the presence of more number of introns in other subfamilies revealed that they are diversifying. Expression profiling of expansin genes showed a distinct expression pattern for biotic and abiotic stress conditions. This study revealed that among the expansin subfamilies, EXPAs contributed significantly towards stress-resistant mechanism. The differential expression of MaEXPA18 and MaEXPA26 under drought stress conditions in the contrasting cultivar suggested their role in drought-tolerant mechanism. Most of the MaEXPA genes are differentially expressed in the root lesion nematode contrasting cultivars which speculated that this expansin subfamily might be the susceptible factor. The downregulation of MaEXPLA6 in resistant cultivar during Sigatoka leaf spot infection suggested that by suppressing this gene, resistance may be enhanced in susceptible cultivar. Further, in-depth studies of these genes will lead to gain insight into their role in various stress conditions in banana.

Supplementary information: The online version contains supplementary material available at 10.1007/s13205-021-03106-x.

Keywords: A and B genome; Banana; Biotic and abiotic stresses; Expansin; Gene expression.