Hamidi Farokh, Karimzadeh Ghasem, Rashidi Monfared Sajad, Salehi Maryam
Department of Plant Genetics and Breeding, Faculty of Agriculture, Tarbiat Modares University , Tehran , Iran.
Department of Agricultural Biotechnology, Faculty of Agriculture, Tarbiat Modares University , Tehran , Iran.
Turk J Biol. 2018 Aug 9;42(4):322-333. doi: 10.3906/biy-1802-86. eCollection 2018.
The species of Artemisia, one of the largest genera of the family Asteraceae, are frequently utilized for the treatment of diseases such as malaria, hepatitis, cancer, inflammation, and infections by fungi, bacteria, and viruses. Karyological studies were performed on 18 Artemisia khorassanica populations: eleven were diploid (2n = 18) and seven were tetraploid (2n = 36). The mean chromosome lengths were 3.61 and 3.84 µm for diploids and tetraploids, respectively. Two chromosome types ("m", "sm") formed karyotype formulas "18m" for diploids and "36m" and "34m + 2sm" for tetraploids. The mean 2C DNA contents were 5.91 and 11.53 pg in diploids and tetraploids, respectively. The transcription levels of key genes involved in artemisinin production were compared in diploid (B, D, H) and tetraploid (O, P, R) A. khorassanica relative to A. annua as a standard species. No artemisinin content was detected in diploid and tetraploid A. khorassanica populations. No significant diefrences were detected between diploids and tetraploids in terms of DXR , HMGR, FDS, and ADS gene expression. This implies that most of the genomic amplification likely occurs in the amount of repetitive DNA and not in unique sequences. The DBR2 gene was expressed in the diploid A. khorassanica in a low amount but silenced in the autotetraploid A. khorassanica.
蒿属是菊科最大的属之一，其物种常用于治疗疟疾、肝炎、癌症、炎症以及由真菌、细菌和病毒引起的感染等疾病。对18个霍拉桑蒿种群进行了核型研究：11个为二倍体（2n = 18），7个为四倍体（2n = 36）。二倍体和四倍体的平均染色体长度分别为3.61和3.84 µm。两种染色体类型（“m”，“sm”）形成了二倍体的核型公式“18m”以及四倍体的“36m”和“34m + 2sm”。二倍体和四倍体的平均2C DNA含量分别为5.91和11.53 pg。以黄花蒿作为标准物种，比较了二倍体（B、D、H）和四倍体（O、P、R）霍拉桑蒿中参与青蒿素生产的关键基因的转录水平。在二倍体和四倍体霍拉桑蒿种群中均未检测到青蒿素含量。在二倍体和四倍体之间，就1-脱氧-D-木酮糖-5-磷酸还原异构酶（DXR）、3-羟基-3-甲基戊二酰辅酶A还原酶（HMGR）、法呢基焦磷酸合酶（FDS）和紫穗槐二烯合酶（ADS）基因表达而言，未检测到显著差异。这意味着大多数基因组扩增可能发生在重复DNA的数量上，而不是在独特序列中。DBR2基因在二倍体霍拉桑蒿中低水平表达，但在同源四倍体霍拉桑蒿中沉默。
