中国四个地方黄牛品种的染色体研究(论文详细摘要)

采用外周血淋巴细胞培养法,以 G-,C-分带和银染技术,对我国4个地方黄牛品种延安地区蒙古牛(10 ♂;5♀)、关中秦川牛(12♂;4),商洛山阳的岭南牛(6♂;5♀)以及陕南西乡的西镇牛(9♂;12)共计63头黄牛的染色体核型,G 带和C 带以及 Ag—NoRs 数目和分布进行了详细的研究。结果发现,性染色体(x 和 y)和     

新型除草剂 Oryzalin 的浓度和处理时间对诱导彩色马蹄莲多倍体的影响*

 用新型除草剂Oryzalin作为彩色马蹄莲体细胞染色体加倍的诱导剂,以愈伤组织芽点为处理材料,研究了不同处理浓度和处理时间的除草剂对彩色马蹄莲染色体加倍的影响。结果表明：以0.0016%的浓度处理36h效果最好,变异率达34%。本研究为培育彩色马蹄莲四倍体新品种,以及进一步检测四倍体植株能否克服马蹄莲种间杂交障碍提供种质资源储备。     

Preliminary analysis of genomic abnormalities in canine meningiomas

Cytogenetic detection of unbalanced genomic aberrations in tumours is a strategy for the identification of tumour suppressor genes and oncogenes. When considered in concert with clinical data, the approach also represents a means of identifying markers of prognosis. In a preliminary investigation of the molecular basis of canine meningioma tumorigenesis, we profiled three tumours by comparative genomic hybridization. Distinct patterns of sub-chromosomal deletions were identified suggesting alternative mechanisms of tumour initiation. The deleted chromosomal segments encompass two regions (10q23.1 and 17q22-q23) that are syntenic to the chromosomes (22 and 1p) most often deleted in human meningiomas. A number of genes associated with DNA repair, cell cycle progression and apoptosis are located on both the deleted canine chromosomal segments and the syntenic regions deleted in human meningiomas. This study represents the first report of chromosomal copy number abnormalities in non-cultured canine brain tumour tissue.     

纤毛鹅观草与多枝赖草属间杂种的细胞遗传学分析(简报)

将纤毛鹅观草与2种不同形态的多枝赖草进行属间远缘杂交,获得杂种F1植株。分析杂种花粉母细胞减数分裂染色体配对行为显示,纤毛鹅观草与多枝赖草的杂种染色体配对频率很低,平均每细胞仅形成1.04和2.09个二价体,平均每细胞染色体交叉数为1.50和4.50,C-值为0.05和0.16。表明鹅观草属的StY基因组与赖草属的NsXm基因组之间的同源程度很低,它们之间亲缘关系甚远。     

外源激素对甘草愈伤组织诱导及染色体加倍的影响(简报)

采用不同浓度配比的外源激素NAA、2,4-D和BAP对甘草不同外植体(子叶、下胚轴和胚根)进行愈伤组织诱导、再生苗分化及细胞染色体加倍的研究。结果表明,不同外植体愈伤组织的诱导频率无差异,均以MS 1.0mg/L NAA 1.0 mg/L 2,4-D 1.0 mg/L BAP培养基的诱导频率最高,均达100%。而再生苗分化具有极显著的差异,以下胚轴最好,在MS 3.0 mg/L BAP 2.0 mg/L ZT 10.0 mg/L GA3培养基上获得的再生苗频率最高,为4.57%。另外,不同外植体类型、不同浓度的NAA、2,4-D对愈伤组织细胞倍性的影响不同,其中下胚轴诱导的四倍体频率明显高于子叶和胚根,平均为42.23%;而1.0 mg/L 2,4-D下的子叶、下胚轴和胚根外植体愈伤组织的四倍体加倍率也达到最高,分别为61.25%,60.00%和58.13%。除此之外,细胞染色体加倍频率随着愈伤组织培养时间的延长而增加。     

梨矮化基因pcDw的SSR标记定位

以矮化梨(Pyrus communis L.)与茌梨(P.bretschneideri Rehd.)的F1杂交分离群体共110个单株(3a生,矮化型和正常型各55株)为试材,对来自西洋梨的矮化型突变基因pcDw进行了SSR分子标记研究。用分离群体分组分析法(Bulked Segregant Analysis,BSA),通过对源自梨、苹果和桃基因组的共40对SSR(Simple Sequence Repeat)引物的筛选,获得了一个与pcDw基因连锁距离为9.3cM的SSR标记KA14210,由此将该基因定位到了梨品种Barlett遗传图谱的第16连锁群上。     

Multiple Avenues to Gender in Strawberries

ABSTRACT

Common strawberry cultivars are hermaphrodites, producing both anthers and pistils in their flowers. However, octoploid Fragaria species are trioecious and different genotypes can be female with pistillate flowers, hermaphrodites, or males with staminate flowers. One female selection, F. virginiana High Falls 22 and three hermaphrodite selections, N8688, RH23, and Montreal River 10 were hybridized with five June-bearing cultivars. Seedlings of each family were planted in Ontario and Michigan. Two F. chiloensis selections Pigeon Point (female) and FRA1267 (hermaphrodite), were hybridized with 14 F. virginiana selections. Seedlings from each family were planted in Ontario and Minnesota. In all progeny, the presence or absence of anthers was recorded and a subjective scale used to estimate the percentage of fruit set (1–10 representing 10% intervals). Also, FRA1267 was crossed with one F. × ananassa selection and the progeny intercrossed and grown in Ontario. In the sib-crosses gender was recorded. In two female parents, the female progeny had on average a higher fruit set than the hermaphrodite progeny. F. virginiana genotypes varied in their fruit set, which suggested that there are a number of alleles involved in the fertility of hermaphrodites. In crosses, FRA1267 produced 80% females when used as a female parent and 100% hermaphrodites when used as a male parent. It is thought that the trait is inherited cytoplasmically or that the F. chiloensis alleles involved are epistatic when F. virginiana or F. × ananassa is used as a male parent.     

Synteny search identifies carnivore Y chromosome for evolution of male specific genes

The explosive accumulation of mammalian genomes has provided a valuable resource to characterize the evolution of the Y chromosome. Unexpectedly, the Y‐chromosome sequence has been characterized in only a small handful of species, with the majority being model organisms. Thus, identification of Y‐linked scaffolds from unordered genome sequences is becoming more important. Here, we used a syntenic‐based approach to generate the scaffolds of the male‐specific region of the Y chromosome (MSY) from the genome sequence of 6 male carnivore species. Our results identified 14, 15, 9, 28, 14 and 11 Y‐linked scaffolds in polar bears, pacific walruses, red pandas, cheetahs, ferrets and tigers, covering 1.55 Mbp, 2.62 Mbp, 964 Kb, 1.75 Mb, 2.17 Mbp and 1.84 Mb MSY, respectively. All the candidate Y‐linked scaffolds in 3 selected species (red pandas, polar bears and tigers) were successfully verified using polymerase chain reaction. We re‐annotated 8 carnivore MSYs including these 6 Y‐linked scaffolds and domestic dog and cat MSY; a total of 11 orthologous genes conserved in at least 7 of the 8 carnivores were identified. These 11 Y‐linked genes have significantly higher evolutionary rates compared with their X‐linked counterparts, indicating less purifying selection for MSY genes. Taken together, our study shows that the approach of synteny search is a reliable and easily affordable strategy to identify Y‐linked scaffolds from unordered carnivore genomes and provides a preliminary evolutionary study for carnivore MSY genes.     

黄花蒿多倍体的诱导与鉴定

利用秋水仙素,采用浸泡法和固体培养法分别对黄花蒿(Artemisia annua L.)丛生芽进行多倍体诱导,以期获得黄花蒿多倍体种质。结果表明,以5 000 mg/L秋水仙素浸泡丛生芽5 d处理获得的诱导效果最好,诱导率可达40%。对性状变异明显的黄花蒿植株进行染色体数目观察,发现了黄花蒿四倍体和嵌合体。