以甜瓜属(Cucumis)黄瓜与酸黄瓜的3种不同倍性异源多倍体—双单倍体种间杂种F1(2n=2x=19,HC)、异源三倍体黄瓜(2n=3x=26,HCC)和异源四倍体C.hytivus(2n=4x=38,HHCC)及其双亲为试材,比较研究过氧化物酶(POD)、谷氨酸脱氢酶(GDH)和天冬氨酸转氨酶(AAT)在不同倍性异源多倍体中的酶谱表达特性,探讨基因组剂量对酶谱表达的影响。结果表明:不同倍性异源多倍体的酶带染色力表现出明显的差异,但酶带数和酶带分布基本一致。在AAT同工酶中,酶带的表达随基因组剂量的提高而增强,在POD和GDH同工酶中,大部分酶带的表达随基因组剂量的提高而减弱。这些结果表明甜瓜属异源多倍体在不同的酶系统中,酶谱表达可能会表现出截然相反的基因组剂量效应。本研究结果可为鉴定甜瓜属异源多倍体和阐述异源多倍体因倍性引起的表型差异提供同工酶证据。
Three alloploids with different ploidies from interspecific hybridization in Cucumis [ interspecific hybrids (2n =2x = 19, HC), allotriploid (2n =3x =26, HCC), and allotetraploid C. hytivus (2n =4x = 38, HHCC) ] and their parents were used for the comparative studies on expression pattern of peroxidase (POD), glutamate dehydrogenase (GDH), and aspartate aminotransferase (AAT). The results showed that the zymograms in the alloploids were similar in band number and band distribution. The intensity of band in these allopolyploids, however, presents significant difference, which was caused by genome dosage. In AAT zymogram, the intensity of band was positively correlated with ploidy level. In POD and GDH zymogram, however, the intensity of band was negatively correlated with ploidy level. It was indicated that the coherence between genome dosage and isozyme expression pattern would be opposite in different enzyme systems. These data will be helpful to illuminate the morphological changes caused by the polyploid level.