Jujube (Ziziphus jujuba Mill.), 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.

枣（Ziziphus jujuba Mill.)，一种落叶乔木，以其药用和营养价值而闻名。作为一种极端微生物，它具有在水资源有限的干旱条件下生存的出色能力。对此，研究枣中水通道蛋白（AQPs）等水分转运调节蛋白的作用具有重要意义。水通道蛋白是一种通道形成蛋白，已知在植物中的水和许多其他小溶质的运输中具有重要作用。在本研究中，计算方法已经确定了 36 个 AQP，其中包括 12 个 NIP（Nodulin 26 样内在蛋白）、10 个 PIP（质膜内在蛋白）、10 个 TIP（液泡膜内在蛋白）、3 个 SIP（​​小内在蛋白）和 1 个 XIP（未表征的内在蛋白）。AQP 的保守特征，如天冬酰胺-脯氨酸-丙氨酸 (NPA) 氨基酸基序，芳香族/精氨酸 (ar/R) 选择性过滤器和 Frogger 残基在溶质特异性和转运中具有重要作用，也被预测。AQP 的基于同源性的三级 (3D) 结构_小号还使用各种工具解决了问题，随后，使用 3D 结构识别了孔隙衬里残留物。孔隙形态信息以及通过这项工作提供的保守特征将有助于预测 AQP 的溶质特异性。转录组数据分析揭示了几种 AQP 在枣不同组织中的组织特异性或普遍表达。有趣的是，发现 TIP3-1 具有水果特异性表达，而大多数 AQP 的表达相对较低。根据目前的研究和以前的报告，TIP3 似乎在种子干燥过程中具有重要作用。此处介绍的研究结果为了解极端微生物特异性 AQP 的功能提供了关键见解，以更好地了解 AQP 的作用以及随后的枣中的应激耐受机制。