【摘要】 MicroRNA156a-SQUAMOSA promoter binding-like protein(miR156a-SPLs)参与植物生长阶段转变、叶片形态建成和逆境胁迫等复杂的生理过程。基于茶树转录组数据,从茶树中克隆出2个SPL家族成员——CsSPL6和CsSPL9。CsSPL6 cDNA全长2 318 bp,ORF框长1 668 bp,编码555个氨基酸;CsSPL9 cDNA全长1 954 bp,ORF框长1 116 bp,编码371个氨基酸;CsSPL6和CsSPL9都有典型SBP结构域和Csn-miR156a识别位点。时空表达特性分析表明,Csn-miR156a在芽中表达量最高,第7叶中最低,与CsSPL6和CsSPL9呈负调控关系;不同品种(系)表达特性分析表明,Csn-miR156a的表达模式与新梢生长量、光合指标结果一致,与CsSPL6和CsSPL9表达模式相反,说明Csn-miR156a、CsSPL6和CsSPL9参与茶树生长过程,Csn-miR156a和CsSPLs可作为初步判断品种生长势强弱的分子手段;高温处理4个品种(系)表达特性表明Csn-miR156a与CsSPL9呈负相关,推断茶树在高温胁迫下Csn-miR156a可能通过负调控CsSPL9来增加耐高温性。Csn-miR156a负调控CsSPLs在茶树生长发育、逆境胁迫中发挥作用,为茶树生长和抗逆机制提供理论依据。更多还原

【Abstract】 Micro RNA156 a-SQUAMOSA promoter binding-like protein(miR156 a-SPLs)play important roles in growth process, formation of leaves and response to stress in tea plant(Camellia sinensis). Based on transcriptome data, two c DNA CsSPL6(2 318 bp) and CsSPL9(1 954 bp) were cloned from tea plant. The nucleotide and amino acid sequences, biological information, phylogenetic tree and molecular expression models of the CsSPL6 and CsSPL9 were analyzed. Sequence analysis showed that the open reading frames of CsSPL6 and CsSPL9 are 1 668 bp and 1 116 bp, encoding 555 and 371 amino acids respectively. Both genes contain typical SBP domain and the recognition sites of micro RNA156 a. Quantitative real-time PCR analysis showed that the expression profile of Csn-miR156 a was the highest in the buds, and the lowest in the 7 th leaves, which was negatively correlated with CsSPL6 and CsSPL9. For different varieties(strains), the expression of Csn-miR156 a was consistent with the growth of new shoots and the value of Photosynthesis index, but negatively correlated with the expression of CsSPL6 and CsSPL9, indicating. Csn-miR156 a,CsSPL6 and CsSPL9 were involved in the growth of tea plant and can be used as markers to assess growth abilities among varieties. In addition, the expression of CsSPL9 was negatively correlatedwith Csn-miR156 a under heat stress in four varieties(strains), which might be associated with the enhanced heat tolerance ability. The results showed that the expression of CsSPLs were negatively regulated by Csn-miR156 a,which played an important role in the growth, development of tea plant and the stress resistance, providing a theoretical basis for understanding the growth and resistance mechanism of tea plant.更多还原