Oligo-FISH涂染揭示柚粗线期1号染色体的结构及配对  

Oligo-FISH painting reveals the structures and pairings of the pachytene chromosome 1 in Citrus maxima

作　　者：何礼[1] 张国艳 陈克玲[1] 何建[1] 关斌[1] 李文婷 刘建军[1] He Li;Zhang Guoyan;Chen Keling;He Jian;Guan Bin;Li Wenting;Liu Jianjun(National-local Joint Engineering Laboratory of Citrus Breeding,Cultivation/Horticulture Institute,Sichuan Academy of Agricultural Sciences,Chengdu 610066,Sichuan,China)

机构地区：[1]柑橘育种与栽培国家地方联合工程实验室·四川省农业科学院园艺研究所,成都610066

出　　处：《果树学报》2023年第4期788-796,共9页Journal of Fruit Science

基　　金：国家自然科学基金项目(32272671);四川省自然科学基金项目(23NSFSC1003);四川省种业重点研发计划项目(2020YFN0146);四川省“十四五”果树育种攻关项目(2021YFYZ0023-02);四川省农业科学院1+9“揭榜挂帅”重点学科领域科技攻关任务(1+9KJGG001,1+9KJGG003)。

摘　　要：【目的】深化柑橘减数分裂粗线期染色体结构组成和配对分析。【方法】首次利用柑橘染色体全长特异寡核苷酸荧光原位杂交(oligo-fluorescence in situ hybridization,oligo-FISH)涂染探针,精准示踪鉴定沙田柚粗线期1号染色体的结构特征,比较其与有丝分裂间期细胞核、有丝分裂前中期和中期染色体的结构差异,并揭示粗线期全长染色体的同源配对。【结果】观测到同源配对的全长粗线期与有丝分裂中期较大染色质结构差异。经测定,柚粗线期1号染色体平均全长、长臂长、短臂长和臂比分别为中期的13.93倍、16.54倍、10.44倍和1.54倍,表现出更高FISH信号分辨率。检测到柚粗线期1号染色体着丝粒附近约3.01 Mb的探针信号缺失区。【结论】首次实现柑橘特定全长粗线期染色体的跟踪研究,为深入开展其结构和配对遗传利用的精准研究提供了新方法。【Objective】The cytogenetic study is not only an important tool for the structural analysis of the chromosomes in Citrus species,but also a direct tool for the pairing investigation of homologous or homeologous chromosomes during meiosis.Then,the precise identification of a specific chromosome,especially a single full-length extended chromosome in meiotic prophaseⅠ,plays a crucial role in realizing the above studies.However,it has been a tough challenge for plant species,let alone most of the non-model plants.Recently,bioinformatically chosen oligonucleotides have been synthesized and labeled as chromosome painting probe libraries in identifying specific portions or entire chromosomes through fluorescence in situ hybridization(FISH).This study aimed to explore and compare the cytogenetic characteristics of a specific citrus chromosome at meiotic pachytene and mitotic stages by chromosome painting with synthesized oligonucleotide probes.【Methods】The representative Citrus species C.maxima(Burm.)Merr.‘Shatian pummelo’(2n=2x=18),cultivated in the experimental base of Horticulture Institute,Sichuan Academy of Agricultural Sciences,Chengdu,China,was used for chromosome painting studies.Firstly,the former bioinformatically chosen and synthesized oligonucleotide library for Citrus chromosome 1-specific FISH painting was labeled as a probe with digoxin.Secondly,the vigorous root tips containing interphase nuclei,prometaphase,and metaphase chromosomes were used for the preparation of mitotic slides. The immature inflorescence was adopted to harvest meioticslides with pachytene chromosomes. Thirdly, both mitotic and meiotic slides were applied for chromosomepainting by oligo-FISH with Citrus chromosome 1-specific oligonucleotide probe. The digoxin-labeledprobe was detected by anti- digoxigenin FITC conjugated antibody (Roche Diagnostics, USA).The chromosomes were counterstained with an antifade solution containing 4’, 6-diamidino-2-phenylindole(DAPI, Vector Laboratories, USA). Finally, the FISH images were ca

关 键 词：柑橘 粗线期 寡核苷酸荧光原位杂交 染色体涂染 分辨率 

分 类 号：S666[农业科学—果树学]