Samatadze T E, Muravenko O M, Bol'sheva N L, Amosova A B, Gostimsckiĭ S A, Zelenin A V
Genetika. 2005 Dec;41(12):1665-73.
The DNA intercalator 9-aminoachridine was used for obtaining high-resolution DAPI patterns of chromosomes of Pisum sativum L. with more than 300 bands per haploid chromosome set. The karyotypes of three pea varieties, Viola, Capital, and Rosa Crown, and two translocation lines, L-108 (T(2-4s)) and M-10 (T(2-7s)), were examined. Based on the results of DAPI staining, we have identified chromosomes, constructed idiograms, and established breakpoints of chromosome translocations. Lines L-108 (T(2-4s)) and M-10 (T(2-7s)) were shown to appear as a result of respectively one translocation between chromosomes 2 and 4 and two translocations between chromosomes 2 and 7. All varieties and translocation lines of pea were examined using fluorescence in situ hybridization (FISH) with telomere repetition probes, 5S and 45S wheat DNA probes. Transcriptional activity of 45S rRNA was detected by Ag-NOR staining. Telomere repetitions were shown to be located only in telomeric chromosome regions. Using high-resolution DAPI staining allowed us to verify localization of 5S genes on pea chromosomes 1, 3, and 5. 45S rDNAs were localized in the secondary constriction regions on the satellite and the satellite thread of chromosome and on the satellite thread and in more proximal satellite heterochromatic region of chromosome 7. The size of 45S rDNA signal on chromosome 7 was larger and its transcriptional activity, higher than the corresponding parameters on chromosome 4 in most of the forms studied. A visual comparison of the results of FISH and Ag-NOR staining of normal and translocated pea chromosomes did not reveal any significant differences between them. The translocations of the satellite chromosomes apparently did not cause significant changes either in the amount of the ribosomal genes or in their transcriptional activity.
DNA嵌入剂9-氨基吖啶被用于获得具有单倍体染色体组中每条染色体有300多条带的豌豆（Pisum sativum L.）染色体的高分辨率DAPI模式。研究了三个豌豆品种（中提琴、首都和玫瑰皇冠）以及两个易位系（L-108（T(2-4s)）和M-10（T(2-7s)））的核型。基于DAPI染色结果，我们鉴定了染色体，构建了核型模式图，并确定了染色体易位的断点。结果表明，L-108（T(2-4s)）和M-10（T(2-7s)）系分别是由于染色体2和4之间的一次易位以及染色体2和7之间的两次易位而出现的。使用端粒重复探针、5S和45S小麦DNA探针通过荧光原位杂交（FISH）对所有豌豆品种和易位系进行了检测。通过银染检测45S rRNA的转录活性。结果表明，端粒重复仅位于染色体的端粒区域。使用高分辨率DAPI染色使我们能够验证5S基因在豌豆染色体1、3和5上的定位。45S rDNA定位于卫星染色体的次缢痕区域以及染色体7的卫星线和卫星丝上，以及卫星线和更靠近近端的卫星异染色质区域。在大多数研究的类型中，染色体7上45S rDNA信号的大小更大，其转录活性也高于染色体4上的相应参数。对正常和易位豌豆染色体的FISH和银染结果进行视觉比较，未发现它们之间有任何显著差异。卫星染色体的易位显然在核糖体基因的数量或其转录活性方面都没有引起显著变化。
