辣椒TPS家族成员的鉴定与CaTPS1的表达分析

利用生物信息学方法,从辣椒全基因组数据库中共鉴定出11个辣椒TPS基因,除Ca TPS3含有1个TPS和2个TPP结构域外,其余分别含有1个TPS和1个TPP结构域。11个Ca TPS分为2类,ClassⅠ包含3个基因(Ca TPS1~Ca TPS3),分别含有16、16和13个内含子,Ca TPS1和Ca TPS2含Motif 1~Motif 5各1个,而Ca TPS3含有2个Motif 4和1个Motif 3。ClassⅡ包含8个基因(Ca TPS4~Ca TPS11),均含有2个内含子,且分别含Motif 1~Motif 6各1个。利用荧光定量PCR对Ca TPS1在辣椒组织表达的特异性和低温应答模式进行分析,结果表明:Ca TPS1在叶片中的表达量大约是根和茎中的5~6倍,说明Ca TPS1的表达具有明显的组织特异性;低温处理后Ca TPS1在根和茎中的表达高峰出现时间明显早于叶片,说明不同组织中Ca TPS1对低温胁迫的应答时间存在一定差异。

Identification of CaTPS Gene Family and Expression Analysis of CaTPS1 in Hot Pepper

Trehalose and the precursor trehalose-6-phosphate participate in responding to abiotic stress as the osmotic regulator and the signaling molecule. Trehalose-6-phosphate synthase（TPS）is one of the most important enzyme among the synthesis mechanism of trehalose-6-phosphate，and plays an important role in the metabolic pathway of trehalose. The over expression of TPS gene can improve crop’s tolerance to abiotic stress. Based on pepper genome database，11 genes of CaTPS family were identified by bioinformatics methods. Besides CaTPS3 contains one TPS and two TPP domains，the rest of 10 CaTPS family genes contain one TPS and one TPP domain. All 11 CaTPS family genes were classified into two classes according to their gene structure and phenogenesis. CaTPS1，CaTPS2 and CaTPS3 are grouped to ClassⅠ. CaTPS1 and CaTPS2 respectively contains 16 introns and 5 motifs from motif 1 to motif 5，while CaTPS3 contains 13 introns，one motif 3 and two motif 4. The rest eight genes from CaTPS4 to CaTPS11  respectively contains two introns and six motifs from motif 1 to motif 6，and they are grouped to ClassⅡ. The expression of tissue specificity and response to low temperature stress of CaTPS1 were analyzed in hot pepper using quantitative real-time PCR. The results showed that the expressive quantity of CaTPS1 gene in leaves were five to six times than that in stems and roots，this indicated that the expression of CaTPS1 appeared obvious tissue specificity in hot pepper. After treated with low temperature，the expressing peak of CaTPS1 in roots and stems appeared earlier than that in leaves，which suggested that the responding times to abiotic stress of CaTPS1 were no accordance between different tissues.