Department of Agronomy, University of Kentucky, Lexington, Kentucky, USA.
Theor Appl Genet. 1970 Jan;40(1):18-25. doi: 10.1007/BF00280982.
Leaf peroxidases of 60 Nicotiana species, 19 cultivars, autopolyploids, interspecific hybrids, and amphidiploids have been compared by polyacrylamide gel block electrophoresis. At least 19 peroxidase bands, four cathodic and 15 anodic, were detected in the species which varied from two bands in N. arentsii to 12 bands in N. tabacum. Tihe cultivars of the latter species failed to reveal any intraspecific variation. Specific difference and varietal resemblance in root peroxidase bands were also observed in nine species and 20 varieties analyzed. Zymograms from autopolyploids and amphidiploids appeared to be identical to that of diploid parents, suggesting that peroxidase banding patterns are independent of ploidy levels. An additive manner of parental peroxidase bands without hybrid enzyme formation in interspecific hybrids and the failure of dissociating peroxidases into subunits lead to a hypothesis that peroxidases in Nicotiana may be controlled by multiple, dominant genes and/or codominant alleles in chromosomes of different genomes. This is in keeping with the lack of relationship between ploidy level and peroxidase banding pattern. Also, species with different chromosome numbers shared many peroxidases in common that possibly reflects a residual homology of peroxidase loci among Nicotiana species. Some species classified in different sections or subgenera but having a common geographic center of origin, showed close similarities in peroxidase zymogram. Results suggest that these species may be closely related in phylogeny, and/or geographic isolation changes the peroxidase genes through mutation and selection. Based on leaf peroxidase zymograms of F 1 hybrids, a putative ancestor of N. tomentosiformis was the progenitor of N. tabacum at its inception.
60 种烟草属物种、19 个品种、同源多倍体、种间杂种和双二倍体的叶过氧化物酶已经通过聚丙烯酰胺凝胶电泳进行了比较。在这些物种中，至少检测到了 19 条过氧化物酶带，其中 4 条阴极和 15 条阳极，从 N. arentsii 的 2 条带到 N. tabacum 的 12 条带不等。后者的品种未能显示出任何种内变异。在分析的 9 个物种和 20 个品种中，也观察到了根过氧化物酶带的特异性差异和品种相似性。自多倍体和双二倍体的同工酶图谱似乎与二倍体亲本的图谱相同，这表明过氧化物酶带型与倍性水平无关。种间杂种中没有杂交酶形成的亲本过氧化物酶带的加性方式以及未能将过氧化物酶分解成亚基，导致一种假设，即烟草属中的过氧化物酶可能由多个显性基因和/或不同基因组染色体的共显性等位基因控制。这与倍性水平与过氧化物酶带型之间缺乏关系是一致的。此外，具有不同染色体数的物种共享许多共同的过氧化物酶，这可能反映了烟草属物种之间过氧化物酶基因座的残余同源性。一些分类在不同节或亚属中的物种，但具有共同的地理起源中心，在过氧化物酶同工酶图谱上表现出密切的相似性。结果表明，这些物种在系统发育上可能密切相关，并且/或者地理隔离通过突变和选择改变了过氧化物酶基因。基于 F1 杂种的叶片过氧化物酶同工酶图谱，推测 N. tomentosiformis 的一个假定祖先可能是 N. tabacum 的原始祖先。
