Centre for Molecular Biotechnology, Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, Moscow, Russia.
PLoS One. 2014 Jan 21;9(1):e85118. doi: 10.1371/journal.pone.0085118. eCollection 2014.
Hemp (Cannabis sativa L.) was karyotyped using by DAPI/C-banding staining to provide chromosome measurements, and by fluorescence in situ hybridization with probes for 45 rDNA (pTa71), 5S rDNA (pCT4.2), a subtelomeric repeat (CS-1) and the Arabidopsis telomere probes. The karyotype has 18 autosomes plus a sex chromosome pair (XX in female and XY in male plants). The autosomes are difficult to distinguish morphologically, but three pairs could be distinguished using the probes. The Y chromosome is larger than the autosomes, and carries a fully heterochromatic DAPI positive arm and CS-1 repeats only on the less intensely DAPI-stained, euchromatic arm. The X is the largest chromosome of all, and carries CS-1 subtelomeric repeats on both arms. The meiotic configuration of the sex bivalent locates a pseudoautosomal region of the Y chromosome at the end of the euchromatic CS-1-carrying arm. Our molecular cytogenetic study of the C. sativa sex chromosomes is a starting point for helping to make C. sativa a promising model to study sex chromosome evolution.
利用 DAPI/C-带染色对大麻（Cannabis sativa L.）进行了核型分析，以提供染色体测量值，并利用针对 45 rDNA（pTa71）、5S rDNA（pCT4.2）、端粒重复序列（CS-1）和拟南芥端粒探针的荧光原位杂交进行了分析。该核型具有 18 条常染色体加上一对性染色体对（雌性为 XX，雄性为 XY）。常染色体在形态上难以区分，但可以使用探针区分出三对。Y 染色体大于常染色体，携带完全异染色质 DAPI 阳性臂和仅在 DAPI 染色较弱的 euchromatic 臂上的 CS-1 重复序列。X 是所有染色体中最大的一条，两条臂都携带 CS-1 端粒重复序列。性二价体的减数分裂构型将 Y 染色体的假常染色体区域定位在携带 euchromatic CS-1 的臂的末端。我们对大麻性染色体的分子细胞遗传学研究为大麻成为研究性染色体进化的有前途的模型奠定了基础。
