黑麦染色体的银染研究

在对黑麦染色体银染过程的盐酸解离条件进行探索的同时,对黑麦染色体的银染正反应区进行了研究,首次发现经短时间空气干燥（4～24 h）的黑麦染色体制片,随着盐酸解离强度的递增,分别出现了核仁组织区(NOR)、NOR和端粒以及NOR和着丝点的银染正反应,就此现象讨论了端粒和着丝点的银染机理。     

黑麦染色体的银染研究

在对黑麦染色体银染过程的盐酸解离条件进行探索的同时,对黑麦染色体的银染正反应区进行了研究,首次发现经短时间空气干燥(4-24h)的黑麦染色体制片,随着盐酸解离强度的递增,分别出现了核仁组织区(NOR)、NOR和端粒以及NOR和着丝点的银染正反应,就此现象讨论了端粒和着丝点的银染机理。     

八倍体小黑麦×普通小麦杂种后代群体中的染色体易位

用改良的Giemsa C-带技术以单株为基础分析了八倍体小黑麦×普通小麦的杂种BC_1,F_(?)和F_(?)代植株的核型。在鉴定了C-带核型的1098株杂种后代植株中,发现了78条小麦-黑麦和277条黑麦-黑麦易位染色体。在不同的世代和株系中,小麦-黑麦染色体易位率变化在4.35—14.07%之间,平均7.10%;黑麦-黑麦染色体易位率在0.48—52.78%之间,平均25.23%。鉴定的小麦-黑麦易位染色体涉及了黑麦的14条不同的染色体臂和小麦的A、B和D组染色体。易位的48.57%发生在小麦和黑麦的部分同源染色体之间,51.43%发生在非部分同源染色体之间。不同的黑麦染色体臂参与易位的频率不同。小麦-黑麦染色体易位主要发生在杂种的早期世代,使用适当的选择技术在F_3获得了纯合的易位植株。文中讨论了快速选育易位系的技术和它们在小麦育种中的应用问题。     

黑麦染色体的带型及其应用

本文利用染色体分带技术,对2个黑麦品种的Giemsa C-带带型进行了分析,提出了黑麦染色体的基本带型。可以看出,黑麦染色体的Giemsa C-带具有以下特点:在所有染色体的短臂末端具有染色深,大而明显的末端带;一部分染色体的长臂末端带较小;着丝点带较浅,在一对染色体上有明显的核仁缢痕带;有的染色体有染色较浅的中间带,这     

黑麦1R染色体的显微分离与回收

建立了利用显微操作技术分离植物单个染色体的方法。以黑麦(Secale cereale L.)为材料,以其标准染色体组型图为依据,识别出黑麦含抗病基因的1R染色体。经显微操作,将单条1R染色体放入Ep-pendorf管中。研究表明,用α-溴奈饱和液对细胞进行预处理,可快速鉴别出黑麦1R染色体。采用去壁低渗制片技术,可明显地改善显微分离单染色体的条件。     

黑麦染色体在小黑麦×小麦F_1花粉植株中的传递

对93株小黑麦×小麦的第一代花粉植株(H_1)进行细胞学观察,并用Giemsa分带技术鉴定其中的黑麦染色体,不同黑麦染色体表现出不同的传递频率。6R最高,1R、3R次之,7R最低。花粉植株中还发现黑麦染色体端体。     

黑麦染色体组有效利用土壤潜在磷基因的遗传分析

以一整套中国春－帝国黑麦二体异附加系为材料用土培盆栽法对黑麦染色体组有效利用土壤潜在磷基因的遗传分析表明,附加帝国黑麦不同染色体对中国春小麦有效利用土壤潜在磷特性具有不同的效应。黑麦１Ｒ、７Ｒ染色体上携带有对该特性有较强促进作用的基因。而５Ｒ染色体上则携带有对该特性具强烈抑制效应的基因     

黑麦1R染色体的显微分离、体外扩增及扩增产物的鉴定

借助Leitz显微操作器,在国产倒置显微镜下(400×)用玻璃针对处于有丝分裂中期的黑麦根尖细胞中的1R染色体成功地进行了分离。分离出来的1R染色体转入0.5 ml的Eppendorf管中,用蛋白酶K处理,把DNA释放出来;经Sau3A酶切,再与人工合成的Sau3A连接头连接;以连接头的一条链的核苷酸顺序片段为引物对DNA酶切片段进行了PCR扩增。琼脂糖凝胶电泳显示扩增产物的长度大约为300~1000 bp。以生物素分别标记的黑麦总体DNA和小麦rDNA为探针进行斑点杂交,结果表明PCR扩增产物确实来源于黑麦的1R染色体DNA。这个方法为构建黑麦1R染色体亚基因组文库和筛选1R染色体特异性探针奠定了基础。     

含有抗白粉病基因的黑麦染色体小片段向小麦的转移

利用感白粉病的小麦品种绵阳11的纯系和黑麦自交系R12杂交, 在其单体附加系自交后代的BC₁F₅株系中选择小麦－黑麦异源易位系。根据已报道的黑麦特异重复序列pSc20H设计了一对特异引物, 用PCR方法鉴定了300个单体附加系的自交BC₁F₅株系,发现其中70个株系含有黑麦染色体成分。一个来源于6R单体附加系的小麦株系96Ⅱ691-830-98表现了对白粉病的高度抗性, PCR方法鉴定证明其含有黑麦染色体成分。对该株系作进一步的基因组原位杂交(GISH)鉴定, 证明它的一对染色体的端部含有黑麦染色体的小片段。这一结果指出, 含有抗白粉病基因的黑麦染色体6R小片段被引入了小麦。研究表明利用单体附加诱导染色体小片段易位是一种有效的方法。利用PCR和GISH原位杂交相结合的方法可提高检测外源染色体小片段的准确性和选择效率。     

黑麦2R染色体的显微分离与回收

建立了利用显微担任技术分离植物单个染色体的方法。以黑麦（Ｓｅｃａｌｅ ｃｅｒｅａｌｅ Ｌ）为材料,以其标准染色体组型图为依据,识别出黑麦含抗病基因的１Ｒ染色体。经显微操作,将单条１Ｒ染色体放入Ｅｐ－ｐｅｎｄｏｆ管中。研究表明,用α－溴萘饱和液对细胞进行预处理,可快速鉴别出黑麦１Ｒ染色体。采用去壁低渗制片技术,可明显地改善显微分离意境染色体的条件。     

Bassam和Sanguinetti银染方法在SRAP和TRAP标记中的比较研究

银染作为一种重要的DNA染色方法,对分子标记检测有重要影响.SRAP标记和TRAP标记是两种较为新型的分子标记,近年来得到了广泛应用,尤其在缺少遗传图谱的物种中应用价值更大.以普通烟草种(Nicotiana tabacum L.)烤烟和香料烟品种作为供试材料,对Bassam和Sanguinetti两种银染方法,在标记检测效率、成本及染色效果等方面进行了研究,并对其在SRAP标记和TRAP标记中的应用进行了探讨.结果表明,Sanguinetti银染法比Bassam银染更为简便、经济,染色照片的色阶图说明Sanguinetti染色方法的背景与扩增带区分明显,能够清楚地读带;且该方法能够扩增出很好的SRAP和TRAP标记谱带.因此,推荐在SRAP和TRAP标记检测中采用Sanguinetti银染方法.     

高碘酸-硝酸银染色法鉴定糖蛋白

对传统的糖蛋白染色方法(高碘酸-Schiff法)进行了改进。蛋白质的氧化采用高碘酸法,染色时采用硝酸银染色法。此方法灵敏度是高碘酸-Schiff法的100倍,而且比高碘酸-Schiff法节省16~18h。     

About the mechanism of interference of silver staining with peptide mass spectrometry

The mechanism by which silver staining of proteins in polyacrylamide gels interferes with mass spectrometry of peptides produced by proteolysis has been investigated. It was demonstrated that this interference increases with time between silver staining and gel processing, although the silver image is constant. This suggested an important role of the formaldehyde used in silver staining development in this interference process. Consequently, a formaldehyde-free staining protocol has been devised, using carbohydrazide as the developing agent. This protocol showed much increased peptide coverage and retained the sensitivity of silver staining. These results were however obtained at the expense of an increased background in the stained gels and of a reduced staining homogeneity.     

An improved technique for selective silver staining of nucleolar organizer regions in human chromosomes

Summary A reliable technique for staining human chromosomal nucleolar organizers (NOR's) with silver solutions is described. The NOR's can be selectively stained dark brown by silver solutions leaving the chromosome arms unstained and available for counterstaining with orcein or Giemsa dyes. Unequivocal identification of chromosome pairs bearing NOR's can be achieved using fluorescent banding techniques followed by silver staining. The silver staining procedure for NOR's was simplified and standardized through control of the chemical and physical conditions during silver impregnation and developing.     

Evidence from studies on segregated nucleoli that nucleolar silver staining proteins C23 and B23 are in the fibrillar component

Several procedures for the silver staining of nucleoli have been evaluated at the electron microscopic level to determine optimal conditions for ultrastructural preservation and staining specificity. The present study shows that a brief fixation with 1% buffered formaldehyde followed by methanol: acetic acid (3 : 1) fixation yielded optimal preservation and silver staining of nucleoli. Using this procedure for electron microscopic studies of interphase nucleoli, it was found that the punctate silver grains observed by light microscopy were composed of fine silver granules, of approx. 100 Å diameter, organized in discrete clusters. In similar studies on adriamycin-induced segregated nucleoli, it was observed that the silver staining reaction was mainly limited to the fibrillar portion of the nucleolus. Accordingly, nucleolar proteins C23 and B23, found earlier to be the major silver binding proteins of the nucleolus, are mainly concentrated in the fibrillar nucleolar component.     

纳米金标记-逐步银染法快速检测金黄色葡萄球菌

将纳米金探针应用于目的核酸的检测,具有与PCR相当的灵敏度和特异性.本研究建立了一种可以在微孔板上快速检测金黄色葡萄球菌的纳米金标记-逐步银染法.该方法利用已包被链霉亲和素的微孔板,将PCR扩增的金黄色葡萄球菌nuc基因与生物素探针、纳米金探针形成的三明治杂交结构锚定其上,然后在低温下逐步银染显色,通过酶标仪检测放大的银染信号.这种纳米金标记-逐步银染法可以在显著降低非特异性背景信号的同时放大银染信号,检测金黄色葡萄球菌nuc基因的灵敏度为1 pmol/L,比常温一步银染法的灵敏度提高约102倍. 51例临床标本的检测结果与PCR法一致,与培养生化鉴定法的检测结果之间无显著性差异(P >0.05). 综上所述,本研究成功构建了金黄色葡萄球菌的纳米金标记-逐步银染法,在病原微生物的快速检测领域表现出广阔的发展潜力.     

Ultrastructural localization of carbohydrates on thin sections of Staphylococcus aureus with silver methenamine and wheat germ agglutinin-gold complex.

Postembedding staining of intracellular carbohydrates on thin sections of Staphylococcus aureus was studied by the silver methenamine and the wheat germ agglutinin-gold techniques. Staining of silver grains was observed on both the cell wall and the cross wall. The staining was interpreted to be due to teichoic acid. Labeling by wheat germ agglutinin-gold particles was observed on both the cell wall and the cross wall, and the staining pattern resembled that of silver methenamine staining. Therefore, the labeling was considered to be due to N-acetylglucosamine of teichoic acid. The combination of two types of cytochemical techniques was useful to localize and characterize the carbohydrates of the bacterial cell.     

Carbon dioxide of air inhibits the formation of silver nanoparticles initiated by proteins in polyacrylamide gel and in solution

It was shown that the staining of proteins in polyacrylamide gel by silver is inhibited by contact with air of the ammonia complex with silver ions used at the first stage of detection. It was proved by experiments on the reduction of silver by ethanolamine from a complex with ethanolamine and by formaldehyde from a complex with ammonia that the formation of silver nanoparticles initiated by proteins is inhibited by air carbon dioxide. The participation of carbon dioxide in this process is discussed. It was found that even the breathing of an experimenter can induce variations in carbon dioxide concentration sufficient to adversely affect the reproducibility of the silver staining techniques. It was concluded that, for stable staining of proteins by silver in polyacrylamide gel, it is necessary to maintain a low concentration of carbon dioxide in air over the detection solutions.     

Silver staining of the nucleolar organizer regions (NORs) in semithin Lowicryl sections

The one-step silver technique was applied to semithin Lowicryl sections of root meristem cells of Allium cepa and a human tumor cell line (TG cells). In vegetal cells, after 5 min of staining reaction, the Ag-NOR proteins formed ring-shaped structures peripherally within the nucleolus. In animal cells silver granules were distributed over the entire nucleolus. The specificity of the staining reaction was increased by incubation of the sections in NH4Cl and Schiff's reagent prior to Ag-NOR silver staining.     

Silver Staining of the Nucleolar Organizer Regions (NORS) in Semithin Lowicryl Sections

The one-step silver technique was applied to semithin Lowicryl sections of root meristem cells of Allium cepa and a human tumor cell line (TG cells). In vegetal cells, after 5 min of staining reaction, the Ag-NOR proteins formed ring-shaped structures peripherally within the nucleolus. In animal cells silver granules were distributed over the entire nucleolus. The specificity of the staining reaction was increased by incubation of the sections in NH₄Cl and Schiff's reagent prior to Ag-NOR silver staining.