天然甘蓝型油菜C染色体组C1,C2缺体的创建及遗传分析  

Development and Genetic Analysis of Two Nullisomic Lines(NC1 and NC2) in Natural Brassica napus

作　　者：蔡梦鲜 高作敏 胡利娟 冯群 王洪程 朱斌 CAI Meng-xian;GAO Zuo-min;HU Li-juan;FENG Qun;WANG Hong-cheng;ZHU Bin(School of Life Sciences,Guizhou Normal University,Guiyang 550001)

机构地区：[1]贵州师范大学生命科学学院,贵阳550001

出　　处：《生物技术通报》2023年第3期81-88,共8页Biotechnology Bulletin

基　　金：国家自然科学基金地区基金项目(32060463);贵州省科学计划项目(QKHJC(2020)1Y102)。

摘　　要：缺体(nullisomic,2(n-1))是相对于正常生物个体(euploid,2n)的染色体组缺失一对同源染色体的有机体,是一种不可多得的遗传材料,能够实现对单条染色体的遗传解析。本研究通过甘蓝型油菜(Brassica napus,2n=38,AnAnCnCn)与先前获得的剥离白菜(restituted B.rapa,RBR,2n=20,AnAn)进行杂交及连续回交,通过C基因组染色体特异分子标记及荧光原位杂交(flourescence in situ hybridization,FISH)技术首次筛选出了甘蓝型油菜C染色体组的两个缺体系:C1染色体(NC1)和C2染色体缺失的缺体系(NC2)。随后对两个缺体材料的花粉母细胞(pollen mathor cell,PMC)观察证实,在终变期的PMC呈现18个二价体,减I后期染色体以18∶18均等分离为主,但在后期I及后期Ⅱ均出现不同频率的落后染色体。与亲本相比,两个缺体的生物量、花粉育性、结实率等显著降低,且表现一些特有性状,例如NC1全叶被覆毛刺,NC2开花时间比亲本提早近两个月,说明缺失染色体上携带有相关性状的抑制基因。这两个缺体材料有效降低了甘蓝型油菜基因组的复杂性,有助于目标性状的初步定位,或者基因定位结果的验证,为今后的甘蓝型油菜遗传研究提供便利。The nullisomic(2(n-1))line losing a pair of chromosome from the normal organism chromosome set has been recognized as a rare and important genetic resources for revealing the missing chromosome.Herein,after screening the offsprings from the cross and backcross between Brassica napus and the restituted B.rapa(RBR,2n =20,AnAn),we used the integration of specific C chromosome molecular markers and fluorescence in situ hybridization technology to screen two nullisomic lines of chromosome C1(NC1) and chromosome C2(NC2) in natural B.napus(2n=38,AnAnCnCn)for the first time.Both two nullisomic lines had 18 bivalents at diakinesis and a dominant segregation of 18∶18 at meiosis anaphase I(MA I)in the pollen mother cells.However,some lagging chromosomes were observed at MA I and MA II in both two lines.Compared to their parental B.napus,the two lines presented significantly smaller phenotype at biomass,pollen stainability,and seed setting,also showed some specific features.For example,the NC1 had the leaves with obvious burrs,and NC2 showed significantly early flowering time of two months earlier than its parental B.napus,indicating some genes inhibited such characters were locating on the missing chromosome.The two nullisomic lines effectively reduce the complexity of B.napus genome,which can be used to map the target traits,or to verify the gene function,and thus to provide convenience for future genetic analysis of B.napus.

关 键 词：缺体 甘蓝型油菜 荧光原位杂交 种质资源 

分 类 号：S565.4[农业科学—作物学]