黑莓果实发育成熟期木质素合成CAD酶及其基因表达  

CAD enzyme activity and gene expression in connection with lignin synthesis during fruit development and ripening process of blackberry

作　　者：张春红[1] 熊振豪 吴文龙[1] 李维林[1,2] ZHANG Chunhong;XIONG Zhenhao;WU Wenlong;LI Weilin(Institute of Botany,Jiangsu Province and Chinese Academy of Sciences,Nanjing 210014,China;College of Forestry,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]江苏省中国科学院植物研究所,江苏南京210014 [2]南京林业大学林学院,江苏南京210037

出　　处：《南京林业大学学报（自然科学版）》2019年第1期141-148,共8页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：国家自然科学基金项目(31600553);江苏省农业科技自主创新项目[CX(17)1004;CX(18)2018];江苏现代农业产业技术体系建设项目(JATS[2018]317)

摘　　要：【目的】比较黑莓高硬度品种‘Arapaho’和低硬度品种‘Boysen’果实发育成熟期木质素合成肉桂醇脱氢酶(CAD)基因表达,及其与CAD酶活性及总木质素含量的关系。【方法】对不同发育时期的黑莓果肉,利用半定量RT-PCR分析18个Ru CADs基因成员的表达,利用比色法测定CAD酶活性,利用滴定法测定总木质素含量。【结果】在黑莓的18个Ru CAD基因成员中,有8个CADs基因成员在2个品种发育早、中期果肉中表达量较高;其中Ru CAD16仅在‘Boysen’的早、中期果肉中表达,而在‘Arapaho’中不表达。‘Arapaho’和‘Boysen’果肉CAD酶活性均在着色前即花后9 d和花后21 d时最高,着色后呈下降趋势。‘Arapaho’和‘Boysen’果肉木质素分别在花后24 d和花后27 d含量较高。【结论】‘Arapaho’和‘Boysen’果实着色后,Ru CADs基因成员表达呈多样化,且硬度与Ru CAD酶及木质素含量关系表现出一定差异;而在果实发育后期,Ru CADs基因表达量降低。CAD酶活性降低及木质素含量下降,与黑莓成熟果实硬度下降具一致性,推测木质素合成与成熟果实硬度形成具有相关性。【Objective】This study aimed to investigate the relationships among the expression profiles of cinnamyl alcohol dehydrogenase( CAD) genes,CAD enzyme activity,and total lignin content in fruit flesh from the fruit-setting to the mature stage of blackberry( Rubus spp.) cv.’Arapaho’and’Boysen’,which had relatively high and low firmness,respectively. 【Method】Expression profiles of Ru CAD genes in the fruit flesh of the two blackberry cultivars during the stages from coloring to maturity were detected using semi-quantitative RT-PCR. The changes in CAD enzyme activity and the lignin contents in fruit flesh were determined by colorimetric and titration methods,respectively. 【Result】During fruit development of the two cultivars,eight Ru CAD genes exhibited high expression level in the early and middle stages.Ru CAD16 was only detected in the early and middle stages in’Boysen’fruit flesh and not found in ’Arapaho’during any developmental stage. CAD enzyme activitly level in’Arapaho’and’Boysen’fruits was higher before coloring,specifically 9 DAF( days after flowering) and 21 DAF,and both declined after coloring. Total lignin content in the fruit flesh of both cultivars increased to relatively high level at 24 DAF and 27 DAF,respectively. 【Conclusion】After fruit coloring,expression level of Ru CAD genes exhibited various patterns,and the relationships among the fruit firmness,CAD enzyme activity and lignin content showed differences in fruits of’Arapaho’and’Boysen’. At late developmental stages,the fruit flesh of’Arapaho’and’Boysen’both showed similar declines in the expression level of Ru CAD genes,CAD enzyme activity,and total lignin contents,which was consistent with the decline in blackberry fruit firmness at maturity,implying a relationship between lignin synthesis and firmness in ripe fruits.

关 键 词：黑莓 果实硬度 肉桂醇脱氢酶(CAD) 基因表达分析 果实发育 

分 类 号：S663.2[农业科学—果树学]