鸭梨PbADC基因的鉴定及在果心褐变中的表达  

Identification and Expression Analysis of PbADC Gene in Core Browning of Yali Pear

作　　者：李庆秀 邓冰 寇晓敏 李萍 吴海清 梁丽雅 闫师杰 Li Qingxiu;Deng Bing;Kou Xiaomin;Li Ping;Wu Haiqing;Liang Liya;Yan Shije(College of Food Science and Biological Engineering,Tianjin Agricultural University,Tianjin 300384;College of Food Science and Engineering,Shanxi Agricultural University,Jinzhong 030801,Shanxi;College of Basic Secience,Tianjin Agricultural University,Tianjin 300384;Tianjin Engineering and Technology Research Center of Agriculural Products Processing,Tianjin 300384;College of Agronomy and Resource Environment,Tianjin Agricultural University,Tianjin 300384)

机构地区：[1]天津农学院食品科学与生物工程学院,天津300384 [2]山西农业大学食品科学与工程学院,山西晋中030801 [3]天津农学院基础科学学院,天津300384 [4]天津市农副产品深加工技术工程中心,天津300384 [5]天津农学院农学与资源环境学院,天津300384

出　　处：《中国食品学报》2023年第11期46-55,共10页Journal of Chinese Institute Of Food Science and Technology

基　　金：国家自然科学基金面上项目(32072278);天津市自然科学基金重点项目(20JCZDJC00420)。

摘　　要：为探究精氨酸脱羧酶(ADC)在鸭梨果心褐变中的调控作用,以鸭梨为材料,对ADC进行鉴定、蛋白生物信息学分析以及基因表达模式分析。结果表明:成功鉴定1个PbADC基因,该基因开放阅读框(ORF)为2193 bp,编码蛋白730个氨基酸残基。系统发育分析表明PbADC蛋白与杜梨、苹果、秋子梨×西洋梨和湖北海棠ADC亲缘关系较近,同源比对结果显示PbADC蛋白包含完整的Orn_Arg_deC_N结构域、精氨酸脱羧酶家族2-磷酸吡哆醛结合位点和2个重要的酶活位点。生物信息学分析显示PbADC为亲水性不稳定蛋白,蛋白分子质量78.403 ku,理论等电点5.23。二级结构以α-螺旋和无规则卷曲为主,不含信号肽和跨膜结构。急速降温处理组的鸭梨果心褐变指数大于缓慢降温处理组。荧光定量PCR及酶活分析结果表明,在鸭梨褐变发生过程中,PbADC基因的表达量出现先升后降的趋势,其表达量与ADC酶活力的变化相吻合。本研究明确了PbADC蛋白的生物信息学特性及PbADC基因在贮藏期间的差异表达,为今后深入开展鸭梨采后果心褐变发生机制研究提供了理论基础。The purpose of this study was to explore the regulatory role of arginine decarboxylase(ADC)in core browning of Yali pear.Using Yali pear as material,the arginine decarboxylase of Pyrus bretschneideri(PbADC)was identified,and the bioinformation of PbADC and the gene expression pattern of PbADC were analyzed.The results showed that the PbADC gene was successfully identified and contained a complete open reading frame of 2193 bp that encoding 730amino acids.The phylogenetic analysis showed that PbADC was very closely to ADC of Pyrus betulifolia,Malus domestica,Pyrus ussuriensis×Pyrus communis and Malus hupehensis,and the multi alignment analysis showed that PbADC containing the complete Orn_Arg_deC_N domain,the binding site of pyridoxal 2-phosphate of ADC family and two important enzyme activity sites.Bioinformatics analysis showed that PbADC was a hydrophilic unstable protein with theoretical isoelectric point of 5.23 and molecular weight of 78.403 ku,which was hydrophilic and non-transmembrane without signal peptide,andα-helix and random coil were the main secondary structure of PbADC.The core browning index of rapid cooling treatment group was higher than that of slow cooling treatment group.Quantitative PCR and enzyme activity results showed that the expression of PbADC increased at the early storange period and then decreased during the browning of Yali pear,and the change of ADC enzyme activity was consistent with the gene expression level.This study clarified the bioinformatics characteristics of PbADC protein and the differential expression of PbADC gene during storage,which provided a theoretical basis for further research on the mechanism of postharvest browning of Yali pear.

关 键 词：鸭梨 褐变 精氨酸脱羧酶基因 基因鉴定 表达分析 

分 类 号：S661.2[农业科学—果树学] TS255.1[农业科学—园艺学]