Changes in T-DNA methylation and expression are associated with phenotypic variation and plant regeneration in a crown gall tumor line.
Changes in T-DNA methylation and expression are associated with phenotypic variation and plant regeneration in a crown gall tumor line.
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T-DNA 甲基化和表达的变化与冠瘿瘤系的表型变异和植物再生有关。
DOI：
10.1007/bf00329940
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Gordon,MP
中科院分区：
文献类型：
--
作者：
Amasino,RM;Powell,AL;Gordon,MP
表型变异的章鱼型冠瘿肿瘤线导致的T-DNA甲基化和表达的模式的变化进行了描述。生长为无组织愈伤组织的变体总是表达T-DNA转录本1和2。在芽形成变异体（畸胎瘤）中，仅表达T-DNA转录本4。该品系还再生了外观正常的生根植物，其中所有T-DNA表达都受到抑制。这些植物的组织需要植物激素才能在体外生长。这些植物是自交的，通过减数分裂传递T-DNA，T-DNA抑制在下一代中保持。在用DNA甲基化、T-DNA转录和植物激素非依赖性肿瘤生长的抑制剂5-氮杂胞苷处理再生的植物组织后，肿瘤生长恢复。不表达T-DNA的细胞系的T-DNA高度甲基化，而5-氮杂胞苷处理的细胞中T-DNA甲基化水平降低，恢复T-DNA表达和植物激素非依赖性生长。T-DNA甲基化程度与T-DNA表达水平之间的相关性表明，甲基化是T-DNA转录抑制的原因。
Phenotypic variation of an octopine-type crown gall tumor line resulting from changes in the pattern of T-DNA methylation and expression is described. Variants that grow as unorganized callus always express T-DNA transcripts 1 and 2. In shoot-forming variants (teratomas) only T-DNA transcript 4 is expressed. This line also regenerates normal-appearing, rooted plants in which all T-DNA expression is suppressed. Tissues from these plants require phytohormones for growth in vitro. These plants are selffertile and transmit T-DNA through meiosis, and T-DNA suppression is maintained in the next generation. After treatment of regenerated plant tissue with 5-azacytidine, an inhibitor of DNA methylation, T-DNA transcription and phytohormone-independent tumorous growth resume. The T-DNA of cell lines in which T-DNA is not expressed is highly methylated, whereas the level of T-DNA methylation is reduced in 5-azacytidine treated cells that resume T-DNA expression and phytohormone-independent growth. The correlation between the degree of T-DNA methylation and the level of T-DNA expression indicates that hypermethylation is responsible for the suppression of T-DNA transcription.