Gene trees and the origins of inbred strains of mice

Extensive data on genetic divergence among 24 inbred strains of mice provide an opportunity to examine the concordance of gene trees and species trees, especially whether structured subsamples of loci give congruent estimates of phylogenetic relationships. Phylogenetic analyses of 144 separate loci reproduce almost exactly the known genealogical relationships among these 24 strains. Partitioning these loci into structured subsets representing loci coding for proteins, the immune system and endogenous viruses give incongruent phylogenetic results. The gene tree based on protein loci provides an accurate picture of the genealogical relationships among strains; however, gene trees based upon immune and viral data show significant deviations from known genealogical affinities.     

Inherited electrophoretic hemoglobin patterns among 20 inbred strains of mice

The hemoglobin from mice of six inbred strains is of the single-spot electrophoretic type, and that from 14 inbred strains is of the diffuse type. No selective advantage is apparent for either type. The distribution among strains shows some relation to the history of the development of the strains.     

Correlation between mean litter size and mean life span among 12 inbred strains of mice

In 12 inbred strains of mice there was no general correlation between litter size and parental life span within strains, although a significant between-strain correlation of +0.69 was found between mean life span of the dams and the mean size of their litters. When data for AKR/J mice, which characteristically die early from leukemia, were excluded, the correlation was increased to +0.90 for the remaining 11 strains. These findings indicate that the correlation is of genetic origin-that is, that genes affecting a dam's life span also affect the size of her litters.     

Brain sensitivity to alcohol in inbred mouse strains

The voluntary selection of aqueous ethanol in preference to water has been studied in a number of animal species. A pharmacological phenomenon observed in all species, including humans, is depression of the central nervous system which eventually leads to "sleep." The sleeping time at a given concentration of alcohol in the brain depends on strain sensitivity.     

Heritability of plasma cholinesterase activity in inbred mouse strains

The activity of cholinesterase was measured in the plasma of 543 mice of both sexes from 23 inbred mouse strains. Differences between strains were highly significant. The heritability of this characteristic was 0.70 in females and 0.67 in males.     

Deficiency of a kidney metalloproteinase activity in inbred mouse strains

Kidneys from BALB/c mice contain a potent metalloendoproteinase, termed meprin, that is active against large proteins as well as small peptides. The enzyme is present in mouse strains C57BR/cdJ, C57BL/6J, BALB/cJ, A/J, DBA/IJ, CD/l, Swiss, and ICR. Three related inbred strains, CBA/J, CBA/CaJ, and C3H/He, are markedly deficient in this enzymatic activity. This is the first report of a heritable deficiency of an intracellular proteinase in mammalian tissues. Meprin deficiency appears to have arisen as an early event in the development of the C stock. Furthermore, meprin is present in the progeny of a cross between a meprin-sufficient female (C57BL/6) and a meprin-deficient male (C3H/HeN), an indication that the trait for the deficiency is recessive.     

近交系小鼠微卫星位点遗传检测方法的建立

笔者设计了 3 4对特异性引物 ,以 PCR方法对部分近交系小鼠基因组微卫星多态性进行了检测和分析 ,在所有 3 4条引物扩增带中 ,有 2 5个微卫星位点的长度在不同品系小鼠中存在差异 ,不同品系小鼠之间微卫星长度多态性差异在3 8.3 %～ 5 8.8%之间。微卫星多态性分析是一种快速、经济的遗传监测近交系动物的方法 ,微卫星位点提供了检测近交系小鼠遗传特性的又一种新的方法     

Rapid increase of phenylethanolamine N-methyltransferase by environmental stress in an inbred mouse strains

The activity of-phenylethanolamine N-methyltransferase in mice of the C57Bl/Ka strain was determined after a 4 degrees C stress. The enzyme activity increased 1.2-fold at the end of 3 hours and by 1.4-fold by the end of 6 hours of the stress. The results are in contrast to those from other species with intact animals in which the enzyme changes only after several days of chronic stress. Cycloheximide prevents the rise in enzyme activity, suggesting the increase may be due to protein synthesis. The increase may provide a model system for studying regulation of catecholamine biosynthetic enzymes.     

DNA指纹技术在近交系小鼠遗传检测中的应用研究

采用生物素标记的(GGAT)4寡核苷酸探针对C57BL/6J、BALB/c和DBA/2三种近交系小鼠进行了DNA指纹图分析.结果表明:(GGAT)4寡核苷酸探针对上述3种近交系小鼠产生的DNA指纹图的图带数均为10-12条,具有良好的多态性,品系内平均DNA指纹图的相似系数在0.92~1.00的范围内,具有相同指纹图的概率均在0.40以上,极显著地高于品系间的相似系数(0.21~0.39)和相同指纹图的概率(P<3.10×10-7),说明(GGAT)4寡核苷酸探针可用于制作近交系小鼠的DNA指纹图,以对其进行遗传检测.     

Antibody to leukemia virus: widespread occurrence in inbred mice

Mice from a wide variety of inbred strains produce immunoglobulin G antibody against murine leukemia virus. This is contrary to the common view that the mouse is immunologically tolerant to its endogenous leukemia virus.     

Hyperprolinemia and prolinuria in a new inbred strain of mice, PRO-Re

A hyperprolinemia was discovered, in a new inbred strain of mice, which was equivalent to about a sevenfold elevation above the concentration of proline in the blood of either of the original parental lines, or of 12 other inbred strains with diverse genetic constitution. In addition, mice of this PRO/Re strain exhibited a marked prolinuria, whereas the other 14 inbred strains had no proline detectable in their urine.     

甘蓝“129”自交不亲和系种子生长发育规律研究

通过对甘蓝"129"自交不亲和系角果和种子生长发育测定研究,结果表明,种荚长和种荚直径在授粉后第30d达最大;种子直径、种荚及种子鲜重在授粉30d后达最大值;种子干重在授粉40d后达最大值;种子发芽率及活力指数在授粉50d后最高.     

Susceptibility to two strains of Friend leukemia virus in mice

A mutant strain of the Friend leukemia virus is described. The parental virus strain, passaged through ICR/Ha mice, shows no or very little activity by the spleen-focus assay in BALB/c mice (by comparison with highly susceptible DBA/2 and ICR/Ha mice) and produces typical Friend disease in these mice only exceptionally; susceptibility to this strain of virus is recessive in the (C57BL/6 x DBA/2) F(1). By contrast, the mutant virus strain is as active in BALB/c mice as in DBA/2 or ICR/Ha mice; susceptibility to the mutant virus strain is dominant in the (C57BL/6 x DBA/2) F(1).     

抗逆性木霉菌株的快速筛选方法

为了高效筛选耐受高温胁迫(36℃),低温胁迫(14℃),盐胁迫(1mol/L NaCl)的木霉菌株,采用12孔板结合菌落面积自动扫描仪,对8种(24株)木霉菌在上述逆境因子下的反应差异进行测定,构建逆境胁迫下优良菌株快速筛选和评价方法。通过相关分析表明,12孔板中菌落直径与相应菌株在9cm平板上的菌落直径呈正相关(P0.05);通过线性回归分析得到,平板上菌落直径(Y)和12孔板中菌落直径(X)的线性回归方程分别为:Y=3.353 X+0.564,(36℃);Y=3.980 X-0.166,(14℃);Y=3.537 X+0.422,(1mol/L NaCl)。与传统筛选方法相比,快速筛选方法可以有效提高筛选效率并减少耗材。本研究关于木霉菌多孔板高效筛选抗逆菌株的技术对于今后科学利用木霉菌资源提供了重要依据和方法。     

IBDV超强毒株、强毒株及疫苗株的快速鉴别诊断

【目的】利用限制性酶切位点的特异性,鉴别IBDV超强毒株、强毒株及疫苗株。【方法】根据IBDVVP2基因的共保守序列设计1对引物,分别以IBDV超强毒株GX8/99、陕西分离株、强毒株(XZ-1、ZZ-1、JL、GX-2、JS-2、SD-1、SD-3、HeN-4、ZJ-1、JX-2、JS-30)和疫苗株(B87、NF8)的VP2保守序列为模板,采用RT-PCR方法扩增VP2基因的共保守序列,并构建IBDV不同毒株的重组质粒。用AhaⅠ/StuⅠ和BamHⅠ/NspⅠ2组限制性内切酶分别对超强毒株、强毒株及疫苗株的重组质粒进行酶切鉴定。【结果】扩增出了IBDVVP2基因中的共保守序列,其长度为802 bp。超强毒株能被AhaⅠ/StuⅠ切出327 bp的片段,而强毒株及疫苗株则能被BamHⅠ/NspⅠ切出270 bp的片段。【结论】此种RT-PCR结合限制性内切酶酶切的鉴别方法能够很好的区分IBDV超强毒株与强毒株和疫苗株。     

Genetic dissection of complex traits with chromosome substitution strains of mice

Chromosome substitution strains (CSSs) have been proposed as a simple and powerful way to identify quantitative trait loci (QTLs) affecting developmental, physiological, and behavioral processes. Here, we report the construction of a complete CSS panel for a vertebrate species. The CSS panel consists of 22 mouse strains, each of which carries a single chromosome substituted from a donor strain (A/J) onto a common host background (C57BL/6J). A survey of 53 traits revealed evidence for 150 QTLs affecting serum levels of sterols and amino acids, diet-induced obesity, and anxiety. These results demonstrate that CSSs greatly facilitate the detection and identification of genes that control the wide diversity of naturally occurring phenotypic variation in the A/J and C57BL/6J inbred strains.     

近交系小鼠5个品系10个微卫星基因位点多态性分析

利用PCR扩增对近交系小鼠5个品系的10个微卫星基因位点进行多态性分析.结果表明,在DDK与B6品系之间有多态性的引物2个,实验室品系和野生小鼠品系之间的差异较大.利用这10个微卫星基因位点可以将5个小鼠品系区分开采,尤其是D14Mit6在5种小鼠品系中表现出更明显特异性.     

西南区应用的7个玉米骨干系与美国自交系的SSR标记分析

利用41对玉米SSR引物对49份美国玉米自交系和7份西南区骨干自交系进行遗传多样性分析,共检测出169个等位基因有变异位点,每对引物检测到等位基因2~10个,平均4.12个;每对SSR引物的多态信息量(PIC值)变化范围为0.299~0.885,平均值为0.652。按UPGMA方法对供试自交系进行聚类,以遗传距离0.572为基准,可将供试材料划分为七类。56份自交系的SSR标记聚类分析表明,78%的美国自交系与西南区常用自交系之间也存在着较大的遗传差异,被单独聚为四类,而22%美国玉米自交系与西南区玉米自交系具有一定的同源性,被聚在第Ⅰ、Ⅳ和Ⅵ类。通过美国玉米种质和西南区应用种质的SSR标记分析,为加强西南区玉米育种材料的改良、创新和利用,以及品种选育提供参考。