Frequent variations in tandem repeats pSc200 and pSc119.2 cause rapid chromosome evolution of open-pollinated rye
Frequent variations in tandem repeats pSc200 and pSc119.2 cause rapid chromosome evolution of open-pollinated rye
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串联重复序列 pSc200 和 pSc119.2 的频繁变异导致开放授粉黑麦染色体快速进化
DOI：
10.1007/s11032-019-1033-0
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发表时间：
2019-09-01
影响因子：
3.1
通讯作者：
Qi, Zengjun
中科院分区：
文献类型：
--
作者：
Guo, Jiangtao;Lei, Yanhong;Qi, Zengjun
异染色质变异被认为在谷物黑麦染色体进化中起重要作用。这一理论仅基于有限数量的样本个体，因为在详细的细胞遗传学分析中很难处理大量样本。在本研究中，我们利用分别代表pSc200和pSc119.2串联重复序列的寡核苷酸TAMRA-oligo-6和fam - psc119.1 -1分析了来自6个开放授粉黑麦品种的300株相对较多的个体。在所有7条染色体上鉴定出73种异染色质块：43种来自pSc119.2, 30种来自pSc200。8个区块类型完全保守，65个（89.04%）的变异频率在0.17 ~ 49.67%之间，平均为14.47%。Block 6R-g3（49.67%）变异频率最高。pSc200基因块类型变异的平均频率（19.33%）高于pSc119.2基因（11.08%）。共鉴定出322条多态性染色体（不同块型的组合），其中79种主要类型的频率高于预期，其中14种频率高出预期5倍。通过对40株小麦-黑麦F1植株的核型分析，确定了6条优先传递染色体。在所调查的300株植物中，每条染色体的杂合度为63.00 ~ 86.66%，异质性为43.66 ~ 90.32%。
Variation in heterochromatin is thought to play an important role in chromosome evolution in cereal rye (Secale cereale). This theory has been based on only limited numbers of sampled individuals, as it is difficult to handle large numbers in detailed cytogenetic analyses. In this study, we analyzed a relatively large number of individuals comprising 300 plants from six open-pollinated rye cultivars using oligonucleotides TAMRA-oligo-6 and FAM-pSc119.2-1 that represent tandem repeats of pSc200 and pSc119.2, respectively. Seventy-three types of heterochromatin blocks were identified on all seven chromosomes: 43 from pSc119.2 and 30 from pSc200. Eight block types were fully conserved, and variants in 65 (89.04%) had frequencies ranging from 0.17 to 49.67% and an average of 14.47%. Block 6R-g3 (49.67%) had the highest frequency of variation. Higher average frequencies of variation in block types were revealed by pSc200 (19.33%) than by pSc119.2 (11.08%). A total of 322 polymorphic chromosomes (combinations of different block types) were identified, including 79 major types with frequencies higher than expected, including 14 that were fivefold higher. Six preferentially transmitted chromosomes were confirmed by karyotype analysis in 40 wheat-rye F1 plants. Among the 300 plants investigated, there were 63.00 to 86.66% heterozygosity and 43.66 to 90.32% heterogeneity for each chromosome.