Abstract：
Water-to-land transition is a hallmark of terrestrialization for land plants and requires molecular adaptation to resist water deficiency. Lineages- or species-specific genes are widespread across eukaryotes, and yet the majority of those are functionally unknown and not annotated. Recent studies have revealed that some of such genes could play a role in adapting to environmental stress responses. Here, we identified a novel gene PpBCG1 (Bryophyte Co-retained Gene 1) in the moss Physcomitrium patens that was responsive to dehydration and rehydration. Under de- and rehydration treatments, PpBCG1 was significantly co-expressed with the dehydrin-encoding gene PpDHNA. Microarray data revealed that PpBCG1 was highly expressed in tissues of spores, female organ archegonia, and mature sporophytes. In addition, the Ppbcg1 mutant showed reduced ability of dehydration tolerance, whose plants were accompanied by a relatively low level of chlorophyll content during recovery. Comprehensive transcriptomics uncovered a detailed set of regulatory processes that were affected by the PpBCG1 disruption. Moreover, experimental evidence showed that PpBCG1 might function in the antioxidant activity, abscisic acid (ABA) pathway, and intracellular calcium (Ca2+) homeostasis to resist desiccation. Together, our study provides insights into the roles of one bryophyte co-retained gene in the desiccation tolerance.
摘要：
水陆过渡是陆地植物陆地化的标志，需要分子适应以抵抗缺水。家族或物种特异性基因在真核生物中普遍存在，然而，其中大多数在功能上是未知的，也没有注释。最近的研究表明，其中一些基因可能在适应环境应激反应中起作用。这里,我们在苔藓中发现了一个新的基因PpBCG1（苔藓共保留基因1），该基因对脱水和补液有反应。在脱水和补液处理下，PpBCG1与脱水蛋白编码基因PpDHNA显著共表达。微阵列数据显示，PpBCG1在孢子组织中高表达，女性器官考古,和成熟的孢子体。此外,Ppbcg1突变体表现出脱水耐受能力降低，在恢复过程中，其植物的叶绿素含量相对较低。综合转录组学揭示了受PpBCG1破坏影响的一组详细的调控过程。此外，实验证据表明，PpBCG1可能在抗氧化活性中起作用，脱落酸（ABA）途径，和细胞内钙（Ca2）稳态以抵抗干燥。一起,我们的研究提供了一个苔藓植物共同保留基因在脱水耐受性中的作用的见解。
