滇重楼种子层积后脱落酸和赤霉素相关基因表达水平的研究

Studies on expression level of genes related to abscisic acid and gibberellic acid in stratified Paris polyphylla var. yunnanensis seeds

目的研究脱落酸(ABA)和赤霉素(GA)相关的6个基因(NCED、CYP707A、ABI2、PP2C、GA20ox2、GA20ox3)在滇重楼种子休眠解除过程中的表达特点。方法分别选取20℃层积和20℃转4℃层积处理后处于不同休眠解除阶段的滇重楼种子为材料,应用实时荧光定量PCR(qRT-PCR)方法分析不同层积处理后6个基因在胚和胚乳中的表达水平。结果在滇重楼种子层积过程中CYP707A、NCED、GA20ox2、GA20ox3和ABI2基因在胚和胚乳中表达有差异,而PP2C表达水平无明显变化规律;CYP707A在低温层积后表达水平显著高于高温层积,尤其是在胚中,而NCED、GA20ox2、GA20ox3和ABI2在高温和低温层积后均有较高的表达水平,且在胚中的表达水平高于胚乳中。结论所筛选出的NCED、CYP707A、ABI2、GA20ox2、GA20ox3基因参与滇重楼种子休眠解除过程,可以作为研究滇重楼种子休眠过程的重要基因。

Objective To clarify the expression profile of six related genes （NCED, CYP707A, ABI2, PP2C, GA20ox2, and GA20ox3） related to abscisic acid （ABA） and gibberellic acid （GA） during the dormancy of Paris polyphylla var, yunnanensis seeds. Methods Using qRT-PCR method to clarify the six gene expression levels in seed embryo and endosperm, which were sampled in different dormancy breaking stages after performing warm （20 ℃） and 20 ℃ turned to cold （4 ℃） seed stratification. Results The CYP707A, NCED, GA20ox2, GA20ox3, and ABI2 genes had different expression profiles in embryo and endosperm while PP2C showed no significant difference. The expression level of CYP707A was higher at cold stratification than that at warm stratification especially in embryo, but the expression levels ofNCED, GA20ox2, GA20ox3, and ABI2 were higher than those at two temperature stratifications, and with higher expression in embryo than that in endosperm. Conclusion The selected ABA and GA related genes （CYP707A, NCED, GA20ox2, GA20ox3, and ABI2） might participate in the seed dormancy breaking and could consider as an important gene for the future research.