‘翠冠’梨大果型芽变的细胞学及相关基因表达研究  

Studies on cytology and related gene expression pattern of a large-fruited bud mutant from ‘Cuiguan' pear (Pyrus pyrifolia)

作　　者：舒莎珊 李鑫[1] 骆军[2] 白松龄[1] 滕元文[1] SHU Shashan LI Xin LUO Jun BAI Songling TENG Yuanwen(Department of Horticulture, Zhejiang University· State Agricultural Ministry Key Laboratory of Horticultural Plant Growth, Development ＆ Quality Improvement, Hangzhou 310058, Zhejiang, China Forestry and Fruit Tree Research Institute, SAAS·Shanghai Key Laboratory of Protected Horticultural Technology, Shanghai 201403, China)

机构地区：[1]浙江大学园艺系.农业部园艺植物生长发育与品质调控重点开放实验室,杭州310058 [2]上海市农业科学院林木果树研究所.上海市设施园艺技术重点实验室,上海201403

出　　处：《果树学报》2017年第6期660-669,共10页Journal of Fruit Science

基　　金：浙江省园艺作物育种先进技术团队项目(2013TD05)

摘　　要：【目的】对造成大果芽变的原因进行探讨。【方法】以‘翠冠’和表现出大果性状的芽变‘潘庄大翠冠’为材料,利用荧光AFLP分子标记进行基因组DNA序列差异分析;用流式细胞仪检测‘潘庄大翠冠’的染色体倍性,用石蜡切片技术进行细胞学观察,用实时荧光定量PCR检测相关基因表达分析。【结果】AFLP分析证实‘潘庄大翠冠’为‘翠冠’的大果芽变,果实内在品质无明显差异。流式细胞检测结果显示,‘潘庄大翠冠’为二倍体,与‘翠冠’相同。‘潘庄大翠冠’梨的细胞分裂期从盛花期开始一直到花后24 d,较‘翠冠’长4 d,花后28 d时,果肉细胞层数显著多于‘翠冠’。细胞周期蛋白D3(cyclin D3,CYCD3)在‘潘庄大翠冠’中的表达量显著高于‘翠冠’。细胞周期蛋白A2(cyclin A2,CYCA2)、细胞周期蛋白依赖性激酶A1(cyclin-dependent kinase A1,CDKA1)和细胞周期蛋白依赖性激酶B2(cyclin-dependent kinase B2,CDKB2)等基因也有表达差异。【结论】‘潘庄大翠冠’确为‘翠冠’的大果芽变,其果实增大的机制并非染色体加倍,而是果实发育过程的细胞分裂期细胞的活跃增殖导致细胞分裂期的延长。【Objective】Fruit size at harvest is determined by both cell number and cell size of flesh which result from cell division and cell expansion processes, respectively. Cell division is regulated by cell cycle. Some important regulatory proteins of cell cycle have been studied, such as cyclins（CYCs） and cyclin-dependent kinases（CDKs）. CDKs control the key transitions in the plant cell cycle. CDKA plays a pivotal role in both the G1-to-S and the G2-to-M transitions, while a reduction in CDKB1 activity results in a block at the G2-to-M transition. Plants contain much more CYCs than previously described in other organisms, some of them have been found to associate with CDKs. D-type cyclins（CYCD） are thought to regulate the G1-to-S transition and function at the G2-to-M transition. A-type cyclins regulate the S-to-M phase, and B-type cyclins control both the G2-to-M transition and the intra-M-phase.To investigate cellular and molecular mechanism related to fruit size in pear,‘Cuiguan＇pear（Pyrus pyrifolia Nakai.） and its spontaneous mutant with larger fruit size（named‘Panzhuang Dacuiguan＇） were used as materials in this study.【Methods】AFLP（amplified fragment length polymorphism） was used to analyze the genomic differences between‘Cuiguan＇and‘Panzhuang Dacuiguan＇. 128 Eco R I/Mse I selective primer pairs were adopted in AFLP analysis. To minimize the effect of low-intensity background peaks（noise）, threshold value for fragment selection were set towards average signal intensity and fragment fre-quency. FCM（flow cytometry） analysis was carried out to record the chromosome ploidy. Genome size wasmeasured using the Otto method. The filtered fluid was then centrifuged at a speed of 5 000 r·min-1for 2min. The system＇s light source of FCM was 488 nm argon lasers. Seasonal changes in longitudinal andtransverse diameters were measured at regular intervals during the course of fruit development. Freshweight, longitudinal diameter and transverse diameter of both‘Cuiguan�

关 键 词：'翠冠’梨 大果型芽变 细胞数目 细胞大小 AFLP 

分 类 号：S661.2[农业科学—果树学]