Abstract:
The global CO2 concentration is predicted to reach 700 µmol·mol-1 by the end of this century. Phoebe bournei (Hemsl.) Yang is a precious timber species and is listed as a national secondary protection plant in China. P. bournei seedlings show obvious photosynthetic decline when grown long-term under an elevated CO2 concentration (eCO2, EC). This decline can be alleviated by high nitrate or ammonium applications. However, the underlying mechanisms have not yet been elucidated. We performed transcriptomic and proteomic analyses of P. bournei of seedlings grown under an ambient CO2 concentration (AC) and applied with either a moderate level of nitrate (N), a high level of nitrate (hN), or a moderate level of ammonium (A) and compared them with those of seedlings grown under eCO2 (i.e., AC_N vs EC_N, AC_hN vs EC_hN, AC_A vs EC_A) to identify differentially expressed genes (DEGs) and differentially expressed proteins (DEPs). We identified 4528 (AC_N vs EC_N), 1378 (AC_hN vs EC_hN), and 252 (AC_A vs EC_A) DEGs and 230, 514, and 234 DEPs, respectively, of which 59 specific genes and 21 specific proteins were related to the regulation of photosynthesis by nitrogen under eCO2. A combined transcriptomic and proteomic analysis identified 7 correlation-DEGs-DEPs genes. These correlation-DEGs-DEPs genes revealed crucial pathways involved in glyoxylate and dicarboxylate metabolism and nitrogen metabolism. The rbcS and glnA correlation-DEGs-DEPs genes were enriched in these two metabolisms. We propose that the rbcS and glnA correlation-DEGs-DEPs genes play an important role in photosynthetic decline and nitrogen regulation. High nitrate or ammonium applications alleviated the downregulation of glnA and rbcS and, hence, alleviated photosynthetic decline. The results of this study provide directions for the screening of germplasm resources and molecular breeding of P. bournei, which is tolerant to elevated CO2 concentrations.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s12298-024-01481-2.
摘要:
预计到本世纪末,全球CO2浓度将达到700µmol·mol-1。菲比·伯恩尼(Hemsl。)杨属珍贵木材树种,被列为我国国家二级保护植物。P.bournei幼苗在CO2浓度升高(eCO2,EC)下长期生长时,光合能力明显下降。这种下降可以通过施用高硝酸盐或铵来缓解。然而,潜在的机制尚未阐明。我们对在环境CO2浓度(AC)下生长的幼苗进行了转录组学和蛋白质组学分析,并应用了中等水平的硝酸盐(N),高水平的硝酸盐(hN),或中等水平的铵(A),并将其与在eCO2下生长的幼苗进行比较(即,AC_N与EC_N,AC_hN与EC_hN,AC_AvsEC_A)来鉴定差异表达基因(DEG)和差异表达蛋白(DEP)。我们确定了4528(AC_N与EC_N),1378(AC_hN与EC_hN),和252(AC_A与EC_A)DEG和230、514和234DEP,分别,其中59个特异基因和21个特异蛋白与eCO2下氮对光合作用的调控有关。组合的转录组和蛋白质组分析鉴定了7个相关-DEGs-DEP基因。这些相关-DEGs-DEPs基因揭示了涉及乙醛酸和二羧酸代谢以及氮代谢的关键途径。rbcS和glnA相关-DEGs-DEPs基因在这两种代谢中富集。我们认为rbcS和glnA相关-DEGs-DEPs基因在光合下降和氮调节中起重要作用。高硝酸盐或铵的应用缓解了glnA和rbcS的下调,因此,缓解光合下降。本研究结果为鲍尔尼种质资源的筛选和分子育种提供了指导,能耐受升高的二氧化碳浓度。
■在线版本包含补充材料,可在10.1007/s12298-024-01481-2获得。