High efficiency production and genomic in situ hybridization analysis of Brassica aneuploids and homozygous plants

Inplantbreedingandgeneticresearch,karyotypicallystablecrosseswhichproducehybridplantshavebeenextensivelyusedtointroduceintocropsthetargettraitsandgenesfromrelatedwildorcultivatedspeciesortoconstructstocksforgeneticanalysis(alienchromosomeadditions,substitutionsandtranslocations)[1—3].Uniparentalgenomeeliminationinkaryotypicallyunstablehybridshasbeenutilizedforhaploidproduction[2,4].Becausetheartificiallysynthesizedallopoly-ploidscannotbeusedascropsformanyreasons,onepurposeofwidehybridizations…     

黄芩的花粉母细胞减数分裂及核型分析

采用压片法,对黄芩花粉母细胞减数分裂及核型进行了研究。结果表明:黄芩的大多数花粉母细胞减数分裂中染色体的行为正常,在终变期同源染色体配对后可形成9个二价体,后期Ⅰ染色体以9∶9的方式向细胞两极分离,其减数分裂为同时型;在少数花粉母细胞减数分裂中观察到落后染色体、染色体桥等异常行为;其花粉粒育性为76.49%。黄芩的染色体数目为2n=2X=18,核型公式为K(2n)=2X=18=16m+2 sm,染色体相对长度组成为2n=1 s+4M1+3M2+1L,其核型为"1A"型。     

果蝇唾液腺染色体试材准备及观察方法的改进

果蝇唾液腺观察实验中大量活体试材的准备与学生剖取腺体的操作是该实验的难点,用甲醇(或乙醇):醋酸=3:1的固定液将果蝇幼虫杀死,变活体解剖为固定后解剖,降低了实验操作的难度;将固定的幼虫置30%的甘油中,放入-20℃冰箱保存,有效地解决了大量优质试材的供给问题,提高了实验教学的效果。     

一个常染色体显性遗传先天性眼外肌 纤维化家系A

为寻找疾病相关基因,通过随访调查、体检、病理检查等手段,发现了一眼外肌纤维化家系4代中有15人患有眼外肌纤维化综合征,主要表现先天性上眼睑下垂、下颌上举、头后仰、双眼固定下转位和被动牵拉试验阳性,眼外肌病理检查结果为肌纤维化和玻璃样变性,所有阳性体征者除眼球运动限制程度有区别外,其他眼部症状基本相同。遗传分析表明,该疾病属常染色体显性遗传。该家系可作为寻找眼外肌纤维化疾病相关基因的宝贵资源。Abstract: To discover novel disease genes, a family with congenital fibrosis of the extraocular muscle was studied by a follow-up investigation, eye examinations and histo-pathological examination. There were fifteen cases suffering from congenital general fibrosis syndrome in four generations. They have congenital blepharoptosis, head tilt, chin lift, primary gaze fixed in a hypo- and exotropic position. The diagnosis is confirmed with positive forced duction testing in the affected eye. Furthermore, fibrosis of the extraocular muscles and hyaline degeneration was confirmed by histo-pathological examination. Except for different levels of restriction of the eyeball movements , other eye symptoms in positive patients are substantially identical. The genetic analysis showed that this disease was caused by autosomal dominant inheritance. The pedigree may be precious resource candidate for discovering disease gene related with congenital fibrosis of the extraocular muscle.     

低温推迟果蝇交配行为的研究

通过不同温度对果蝇羽化至交配时间的影响试验,发现在5℃、10℃条件下果蝇雌雄混存, 处女蝇的安全期可由8 h分别延长到72 h、48 h以内。     

麦蓝菜的花粉母细胞减数分裂及核型分析

采用压片法,对麦蓝菜的花粉母细胞减数分裂及体细胞核型进行了研究。结果表明,麦蓝菜的绝大多数花粉母细胞减数分裂中染色体的行为正常,在终变期同源染色体配对后可形成15个二价体;在少数花粉母细胞减数分裂中观察到落后染色体、染色体桥等异常行为;其减数分裂为同时型,其花粉粒育性为88.04%。麦蓝菜的染色体数目为2n=2X=30,核型公式为K(2n)=2X=30=22m(2SAT)+8 sm,染色体相对长度组成为2n=16M2+14M1,其核型为"1A"型。     

High efficiency production and genomic<Emphasis Type="Italic">in situ</Emphasis> hybridization analysis of<Emphasis Type="Italic">Brassica</Emphasis> aneuploids and homozygous plants

Interspecific and intergeneric hybridizations have been widely used in plant genetics and breeding to construct stocks for genetic analysis and to introduce into crops the desirable traits and genes from their relatives. The intergeneric crosses between Brassica juncea (L.) Czern. & Coss., B. carinata A. Braun and Orychophragmus violaceus (L.) O. E. Schulz were made and the plants produced were subjected to genomic in situ hybridization analysis. The mixoploids from the cross with B. juncea were divided into three groups. The partially fertile mixoploids in the first group (2n = 36-42) mainly contained the somatic cells and pollen mother cells (PMCs) with the 36 chromosomes of B. juncea and additional chromosomes of O. violaceus. The mixoploids (2n = 30-36) in the second and third groups were morphologically quite similar to the mother plants B. juncea and showed nearly normal fertility. The plants in the second group produced the majority of PMCs (2n = 36) with their chromosomes paired and segregated normally, but 1-4 pairs of the O. violaceus chromosomes were included in some PMCs. The plants in the third group produced only PMCs with the 36 B. juncea chromosomes, which were paired and segregated normally. The mixoploids (2n = 29-34) from the cross with B. carinata produced the majority of PMCs (2n = 34) with normal chromosome pairing and segregation, but some plants had some PMCs with 1-3 pairs of chromosomes from O. violaceus and other plants had only PMCs with the B. carinata chromosomes. The Brassica homozygous plants and aneuploids with complete or partial chromosome complements of Brassica parents and various numbers of O. violaceus chromosomes were derived from these progeny plants. The results in this study provided the molecular cytogenetic evidence for the separation of parental genomes which was previously proposed to occur in the hybridizations of these two genera.     

乙醚、乙醇用于果蝇麻醉的研究

在以果蝇成虫为材料的实验中,麻醉剂的使用剂量是实验成功与否的重要环节。本研究结合乙醚、无水乙醇2种麻醉剂的特点,筛选出了乙醚-无水乙醇复合麻醉的最佳剂量。经比较认为：乙醚：无水乙醇=1：1的配方具有安全范围宽、麻醉效果好的特点。并给出了其麻醉剂量、麻醉处理时间及其对应的麻醉效果等翔实的数据。有很好的实用性。     

高频率产生芸苔属非整倍体和纯合植株及基因组原位杂交分析

进行了芥菜型油菜(Brassica juncea (L.) Czern. &; Coss.)和埃塞俄比亚芥(B. carinata A. Braun)与新油料植物资源诸葛菜(Orychophrogmus violaceus (L.) O. E. Schulz)之间的属间杂交, 并对产生的后代植株进行了基因组原位杂交分析. 结果表明, 芥菜型油菜与诸葛菜的杂交后代由3类混倍体组成, 第一类的体细胞和花粉母细胞(PMC)主要含有芥菜型油菜的36条染色体和附加的诸葛菜染色体(2n = 36 ~ 44); 第二类(2n = 30 ~ 36)主要产生具有芥菜型油菜染色体的PMC(2n = 36)和1 ~ 4对芥菜型油菜染色体被诸葛菜染色体所代换的代换型PMC(2n = 36); 第三类(2n = 30 ~ 36)植株的PMC则只具有芥菜型油菜染色体(2n = 36). 而埃塞俄比亚芥与诸葛菜的杂交后代由两类混倍体(2n= 29 ~ 34)组成, 第一类的绝大多数PMC的染色体数目(2n= 34)及行为与母本埃塞俄比亚芥植株的一样, 只是部分PMC包含1 ~ 3对诸葛菜染色体, 而第二类的PMC只具有埃塞俄比亚芥的34条染色体. 从以上杂种的后代中获得了芸苔属亲本种的附加系、代换系、 亚倍体和纯合植株. 这些结果为在芸苔属与诸葛菜属间杂交中可能发生的亲本种染色体组分开现象提供了分子细胞遗传学证据.