Wei Meiying, Wang Bo, Li Chaoqun, Li Xiaolan, He Cai, Li Yi
College of Forestry, Gansu Agricultural University, Lanzhou, China.
Front Genet. 2024 Oct 1;15:1474259. doi: 10.3389/fgene.2024.1474259. eCollection 2024.
Bobr., a prominent xerophytic shrub, exhibits remarkable adaptability to harsh environment and plays a significant part in preventing desertification in northwest China owing to its exceptional drought and salinity tolerance.
To investigate the drought-resistant mechanism underlying , we treated 8-week-old seedlings with polyethylene glycol (PEG)-6000 (20%, m/m) to induce drought stress. 27 samples from different tissues (leaves, roots and stems) of at 0, 6 and 24 h after drought stress treatment were sequenced using PacBio single-molecule real-time (SMRT) sequencing and Illumina RNA sequencing to obtain a comprehensive transcriptome.
The PacBio SMRT sequencing generated 44,829 non-redundant transcripts and provided valuable reference gene information. In leaves, roots and stems, we identified 1162, 2024 and 232 differentially expressed genes (DEGs), respectively. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that plant hormone signaling and mitogen-activated protein kinase (MAPK) cascade played a pivotal role in transmitting stress signals throughout the whole plant following drought stress. The interconversion of starch and sucrose, as well as the biosynthesis of amino acid and lignin, may represent adaptive strategies employed by to effectively cope with drought. Transcription factor analysis showed that and families were mainly involved in the regulation of drought response genes. Furthermore, eight physiological indexes, including content of proline, hydrogen peroxide (H2O2), malondialdehyde (MDA), total amino acid and soluble sugar, and activities of three antioxidant enzymes were all investigate after PEG treatment, elucidating the drought tolerance mechanism from physiological perspective. The weighted gene co-expression network analysis (WGCNA) identified several hub genes serve as key regulator in response to drought through hormone participation, ROS cleavage, glycolysis, TF regulation in .
These findings enlarge genomic resources and facilitate research in the discovery of novel genes research in , thereby establishing a foundation for investigating the drought resistance mechanism of xerophyte.
梭梭是一种著名的旱生灌木，对恶劣环境具有显著的适应性，由于其出色的耐旱和耐盐性，在中国西北沙漠化防治中发挥着重要作用。
为了探究梭梭的抗旱机制，我们用聚乙二醇（PEG）-6000（20%，m/m）处理8周龄的梭梭幼苗以诱导干旱胁迫。在干旱胁迫处理后的0、6和24小时，从梭梭不同组织（叶、根和茎）采集27个样本，使用PacBio单分子实时（SMRT）测序和Illumina RNA测序进行测序，以获得全面的转录组。
PacBio SMRT测序产生了44,829个非冗余转录本，并提供了有价值的参考基因信息。在叶、根和茎中，我们分别鉴定出1162、2024和232个差异表达基因（DEG）。京都基因与基因组百科全书（KEGG）分析表明，植物激素信号传导和丝裂原活化蛋白激酶（MAPK）级联在干旱胁迫后在整个梭梭植株中传递胁迫信号方面发挥着关键作用。淀粉和蔗糖的相互转化，以及氨基酸和木质素的生物合成，可能是梭梭有效应对干旱所采用的适应性策略。转录因子分析表明，AP2/ERF和MYB家族主要参与干旱响应基因的调控。此外，在PEG处理后，对包括脯氨酸、过氧化氢（H2O2）、丙二醛（MDA）、总氨基酸和可溶性糖含量以及三种抗氧化酶活性在内的八个生理指标进行了研究，从生理角度阐明了耐旱机制。加权基因共表达网络分析（WGCNA）确定了几个枢纽基因，这些基因通过激素参与、ROS清除、糖酵解、转录因子调控等在梭梭响应干旱中作为关键调节因子。
这些发现扩大了基因组资源，促进了梭梭新基因发现的研究，从而为研究旱生植物的抗旱机制奠定了基础。
