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1.
Genetic analysis of a proposed cis-acting temporal locus ( Adh-3t ), which regulates alcohol dehydrogenase C2 (ADH-C2 ) acitivity in mouse epididymis extracts, among F1 (ddN × BALB/c) × ddN male backcross progeny provided evidence for genetic distinctness between the structural ( Adh-3 ) and temporal ( Adh-3t ) loci on chromosome 3. Genetic analysis also confirmed the close, linkage of Adh-1 (encoding liver and kidney ADH-A2 ) and Adh-3 (encoding stomach ADH-C2 ) to within 0.3 centimorgans on the mouse genome. Evidence is presented for a proposed closely linked cis-acting temporal locus (designated Adh-1t ) for the A2 isozyme (encoded by Adh-1 ) controlling the activity of this enzyme in mouse kidney extracts, but having no apparent affect on liver and intestine ADH-A2 activities. An extensive survey of the distribution of Adh-1, Adh-3 and Adh-3t alleles among 65 strains of mice is reported — with the exception of two Japanese strains (ddN and KF), linkage disequilibrium between Adh-3 and Adh-3t was observed. Sex differences in mouse liver and kidney ADH-A2 activities were observed, with male/female ratios of approximately 0.6 and 3 respectively for these tissue extracts. 相似文献
2.
Hungtu Ma Minghong Gu G. H. Liang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(3):389-394
Summary Immature embryos of 20 sorghum genotypes were cultured on MS 5 medium containing MS mineral salts supplemented with 2,4-D, zeatin, glycine, niacinamide, Ca-pantothenate, L-asparagine, and vitamins. For regeneration, calli were transferred onto the same medium with the exception that IAA was substituted for 2,4-D. In general, immature embryos obtained 9–12 days after pollination resulted in the best redifferentiation. Ability of calli to regenerate varied among genotypes; cultivars C401-1 and C625 had the highest redifferentiation frequencies. Ability to redifferentiate was heritable and acted as a dominant trait. At least two gene pairs were involved. Regenerated R0 plants were planted in a greenhouse and their selfed (R1 and R2) progenies were planted in the field and examined for morphological and cytological variations. The majority of the phenotypic variations noted in R0 were not transmitted to later generations. However, variants for plant height, degree of fertility, and midrib color persisted in R1 and R2 generations. A variation in tallness was attributable to one dominant mutant gene. Short stature and male sterility variants appeared to be consequences of recessive mutant genes controlling those traits. Minor variations in peroxidase banding patterns were found among R0 plants.This study was supported by a research grant from Kansas Sorghum Commission and by a Research Fellowship to the senior author from the Ministry of Agriculture, Animal Husbandry, and Fisheries, China. Contribution 86-456-J from the Kansas Agricultural Experiment Station 相似文献
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J. W. Kadereit 《Plant Systematics and Evolution》1991,175(1-2):93-99
The genomic evolution of triploid plants with regular bivalent formation is discussed. The conclusion is reached that although all the progeny of an originally triploid individual will be triploid numerically, only part of the progeny will be triploid genomically. The consequences of this for triploid identification by means of chromosome morphology and isozyme numbers is discussed. 相似文献
6.
The F2 progeny of a cross between a chromosome 2 multiple marker stock and an adapted cultivar of barley were analyzed for four
morphological markers and electrophoretic patterns of eight leaf isozymes. TheIdh-2 locus was linked to thePer-5 locus (27.96±5.07 cM) and to thee locus (10.26±3.13 cM). Also, thePer-5 ande loci were located on the short arm of chromosome 2. In additionIdh-2 was also located on barley chromosome 2 and was linked to thev locus (13.18±3.56 cM), which is located on the long arm of chromosome 2. Two other marker genes,li andwst,,B, were linked (26.50±5.24 cM) on chromosome 2 but segregate independently of the other loci evaluated.
This project was supported by funds from the U.S.-Spain Joint Committee for Scientific and Technological Cooperation. 相似文献
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An electrophoretically unique, thermolabile isozyme of triosephosphate isomerase (TPI; EC 5.3.1.1) accounts for 10–30% of the enzymatic activity in a range of mitotically active human cells and tissues. This type 2 form (subunit) of human TPI appears in two isozymes, an anodally migrating, relative to the constitutive TPI-1/1 homodimer, TPI-2/2 homodimer and the TPI-1/2 heterodimer with an intermediate mobility. Human cell types expressing the induced isozyme, which is the product of the same structural locus as the constitutive isozyme, include mitogen-stimulated lymphocytes, virally transformed B-lymphoblastoid cells, leukemia-derived T-lymphoblastoid cells, HeLa cells, both normal and transformed fibroblasts, and placental tissue. Extracts of nondividing or terminally differentiated human cells/tissues, such as erythrocytes, striated muscle, peripheral lymphocytes, and platelets, contain high levels of the constitutive TPI-1/1 isozyme but little or undetectable levels of the TPI-1/2 or TPI-2/2 isozyme. The cell division-associated TPI-1/2 and -2/2 isozymes are distinct in electrophoretic mobility from the deamidated forms of the constitutive isozyme. Extracts of dividing gorilla fibroblasts display an isozyme pattern identical to that of proliferating human cells, but various proliferating cells derived from the African green monkey, rabbit, and chicken express only the constitutive isozyme. Thus, expression of the cell division-associated isozyme of TPI is restricted to the hominoids, suggesting a recently evolved modification mechanism which is specifically activated in proliferating cells.Financial support was derived from Contract EY-77-C-02-2828 from the Department of Energy and Training Grant 5-T32-GM07544 from the National Institutes of Health. 相似文献
9.
NAD~+-MDH在黄瓜子叶中的定位是细胞溶质中占总活性的55~59%,线粒体为38~35%,叶绿体为7%。其同工酶谱亦为细胞溶质中带数最多,全青为5条,粤早3号为4条,线粒体和叶绿体均为1条,品种间无明显差异。黄瓜幼苗随低温胁迫的加剧,伤害逐步加重,子叶电解质渗出率明显增加,NAD~+-MDH活性亦不断下降,其中叶绿体的NAD~+-MDH对低温最敏感,1±1℃处理就能反映品种间耐寒力的差异。叶绿体和线粒体的NAD~+-MDH同工酶对低温的反应与活性变化一致,谱带数没有差异,只是活性降低。细胞溶质部分酶带较多,各条酶带对低温的反应不同。 相似文献
10.
杂交水稻及三系在发育过程中的酯酶同工酶比较研究 总被引:7,自引:1,他引:6
刘文芳;吴文瑜;肖翊华 《武汉植物学研究》1987,5(3):267-274
本文报道了利用聚丙烯酰胺凝胶电泳技术,测定杂交水稻及三系亲本共50个组合的萌动胚、芽,不同发育时期的叶片、根、雄蕊等12个组织或器官的酯酶同工酶的结果。根据所测结果,可把杂交水稻的酯酶同工酶酶谱分为5种类型:互补型、偏父型、偏母型、同型和“杂种”酶谱。强优势组合以互补型酶谱居多,弱优势组合都是同型酶谱,“杂种”酶谱仅见于V优64的幼穗分化期叶片和V优63、汕优63的三叶期叶片中。不同器官的互补酶谱都可作为预测杂种比势,鉴定杂交稻种子的纯度和真实性以及选配新杂交组合的一个手段或依据,但以对萌动胚或幼芽的测定更有实践意义。 相似文献