Understanding aquaporin transport system in highly stress-tolerant and medicinal plant species Jujube (Ziziphus jujuba Mill.)

Nirbhay Kumar; Surbhi Kumawat; Praveen Khatri; Pankaj Singla; Gitanjali Tandon; Vacha Bhatt; Suhas Shinde; Gunvant B Patil; Humira Sonah; Rupesh Deshmukh

doi:10.1016/j.jbiotec.2020.09.026

Understanding aquaporin transport system in highly stress-tolerant and medicinal plant species Jujube (Ziziphus jujuba Mill.)

J Biotechnol. 2020 Dec 20:324:103-111. doi: 10.1016/j.jbiotec.2020.09.026. Epub 2020 Sep 29.

Authors

Affiliations

¹ National Agri-Food Biotechnology Institute (NABI), Mohali, India.
² National Agri-Food Biotechnology Institute (NABI), Mohali, India; Department of Biotechnology, Panjab University, Chandigarh, India.
³ School of Biosciences, Institute of Management Studies, Ghaziabad, India.
⁴ Department of Botany, Savitribai Phule Pune University, Pune, India.
⁵ Department of Biology and Gus R. Douglass Institute, West Virginia State University, Institute, WV, USA.
⁶ Department of Plant and Soil Science, Institute for Genomics of Abiotic Stress Tolerance, Texas Tech University, Lubbock, TX, USA.
⁷ National Agri-Food Biotechnology Institute (NABI), Mohali, India. Electronic address: rupesh0deshmukh@gmail.com.

PMID: 33007348
DOI: 10.1016/j.jbiotec.2020.09.026

Abstract

Jujube (Ziziphus jujubaMill.), a deciduous tree, is well known for its medicinal and nutritional values. Being an extremophile, it has an excellent capability to survive under arid conditions with limited water availability. In this regard, studying the role of water transport regulating proteins such as Aquaporins (AQPs) in jujube is of great importance. Aquaporins, channel-forming proteins are known to have a significant role in the transport of water and many other small solutes in plants. In the present study, computational approaches have identified 36 AQPs, which comprised of 12 NIPs (Nodulin 26-like intrinsic proteins), 10 PIPs (Plasma membrane intrinsic proteins), 10 TIPs (Tonoplast intrinsic proteins), 3 SIPs (Small intrinsic proteins), and 1 XIP (uncharacterized intrinsic protein). Conserved features of AQPs like asparagines-proline-alanine (NPA) amino acid motifs, aromatic/arginine (ar/R) selectivity filters, and Frogger's residues, having a significant role in solute specificity and transport, were also predicted. Homology-based tertiary (3D) structures of AQP_S were also resolved using various tools, and subsequently, pore-lining residues have been identified using the 3D structures. The information of pore morphology, along with the conserved features provided through this work, will be helpful to predict solute specificity of AQPs. Analysis of transcriptomic data revealed the tissue-specific or ubiquitous expression of several AQPs in different tissues of jujube. Interestingly, TIP3-1 was found to have fruit specific expression whereas most of the AQPs have a relatively low expression. Based on the present study and previous reports, TIP3s seems to have a significant role in seed desiccation processes. The findings presented here provide pivotal insights into the functions of extremophile specific AQPs, to better understand the role of AQPs and, subsequently, the stress tolerance mechanism in jujube.

Keywords: Aquaporin proteins; Gene expression; Gene family evolution; Jujube; Solute specificity; Tertiary structure.

MeSH terms

Aquaporins* / genetics
Fruit / metabolism
Phylogeny
Plant Proteins / genetics
Plant Proteins / metabolism
Plants, Medicinal*
Vacuoles / metabolism
Ziziphus* / metabolism

Substances

Aquaporins
Plant Proteins