College of Forestry, Sichuan Agricultural University, Huimin Road 211, Wenjiang District, Chengdu 611130, China.
Genes (Basel). 2019 Nov 7;10(11):904. doi: 10.3390/genes10110904.
R.H. Chang & C.S. Ding is a good horticultural tree because of its beautiful yellow flowers and evergreen leaves. In this study, fluorescence in situ hybridization (FISH) was used to analyse mitotic metaphase chromosomes of with 5S rDNA and (AGT) oligonucleotides. Twenty-two small chromosomes were observed. Weak 5S rDNA signals were observed only in proximal regions of two chromosomes, which were adjacent to the (AGT) proximal signals. Weak (AGT) signals were observed on both chromosome ends, which enabled accurate chromosome counts. A pair of satellite bodies was observed. (AGT) signals displayed quite high diversity, changing in intensity from weak to very strong as follows: far away from the chromosome ends (satellites), ends, subtelomeric regions, and proximal regions. Ten high-quality spreads revealed metaphase dynamics from the beginning to the end and the transition to anaphase. Chromosomes gradually grew larger and thicker into linked chromatids, which grew more significantly in width than in length. Based on the combination of 5S rDNA and (AGT) signal patterns, ten chromosomes were exclusively distinguished, and the remaining twelve chromosomes were divided into two distinct groups. Our physical map, which can reproduce dynamic metaphase progression and distinguish chromosomes, will powerfully guide cytogenetic research on and other trees.
R.H. Chang & C.S. Ding 是一种很好的园艺树种，因为它的黄花和常绿的叶子都很美丽。在这项研究中，荧光原位杂交（FISH）被用于分析具有 5S rDNA 和（AGT）寡核苷酸的 有丝分裂中期染色体。观察到二十二条小染色体。只有两条靠近（AGT）近端信号的近端区域观察到弱的 5S rDNA 信号。在染色体的两端观察到弱的（AGT）信号，这使得准确的染色体计数成为可能。观察到一对卫星体。（AGT）信号显示出相当高的多样性，从弱到强的强度变化如下：远离染色体末端（卫星）、末端、端粒区域和近端区域。十个高质量的展开揭示了从中期开始到结束以及向后期转变的中期动力学。染色体逐渐变成更大更厚的连接染色单体，宽度的增长比长度的增长更为显著。基于 5S rDNA 和（AGT）信号模式的组合，可将十条染色体区分开来，其余十二条染色体分为两组。我们的物理图谱可以重现动态的中期进展并区分染色体，这将有力地指导 及其它树木的细胞遗传学研究。
