A reciprocal translocation, induced by a canonical integration of a single T-DNA, interrupts the HMG-I/Y Arabidopsis thaliana gene
A reciprocal translocation, induced by a canonical integration of a single T-DNA, interrupts the HMG-I/Y Arabidopsis thaliana gene
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DOI：
10.1016/j.plaphy.2004.01.003
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发表时间：
2004-03-01
影响因子：
6.5
通讯作者：
Picard, G
中科院分区：
文献类型：
--
作者：
Lafleuriel, J;Degroote, F;Picard, G
主要染色体重排发生在拟南芥 T-DNA 转化过程中。它们通常是由整合过程中多个 T-DNA 拷贝之间的相互作用或中止的整合事件引起的。我们在这里报告了与单个 T-DNA 整合相关的相互易位，否则显示了典型整合事件的所有特征。交换的片段大致对应于 1 号染色体左臂的一半和 2 号染色体右臂的三分之二。 I 号染色体断点位于位置 23.6 cM 附近，中断了 HMG-I/Y 基因的编码序列，该基因在拟南芥基因组中以单个拷贝存在，编码一种推测参与基因表达调节的非组蛋白染色体蛋白。 2 号染色体断点位于位置 33.6 cM 附近，位于编码推定同源域转录因子的基因上游 419 bp。易位的纯合子表现出严重的表型，具有严重的发育异常和完全不育，而杂合子则具有可育性，其中大多数表现出野生型表型。在六种可能的不平衡基因型类别中，四种是完全致命的，而另外两种中只有少数个体存活下来。表型和基因型之间关系的分析强烈表明观察到的主要表型改变不是由HMG-I/Y基因失活引起的。 (C) 2004 年爱思唯尔 SAS。版权所有。
Major chromosomal rearrangements occur during Arabidopsis thaliana T-DNA transformation. They generally result from interactions between multiple T-DNA copies during the integration process or from aborted integration events. We report here a reciprocal translocation associated with the integration of a single T-DNA which otherwise shows all the characteristic features of a canonical integration event. The exchanged fragments roughly correspond to half of the left arm of chromosome 1 and to two thirds of the right arm of chromosome 2. The chromosome I breakpoint maps close to position 23.6 cM and interrupts the coding sequence of the HMG-I/Y gene, which is present at a single copy in the Arabidopsis genome and encodes a non-histone chromosomal protein putatively involved in regulation of gene expression. The chromosome 2 breakpoint maps close to position 33.6 cM, and is located 419 bp upstream of a gene encoding a putative homeodomain transcription factor. Homozygotes for the translocation display a severe phenotype with major developmental abnormalities and total sterility, while heterozygotes are fertile, most of them showing a wild-type phenotype. Among the:six possible unbalanced genotypic classes, four are entirely lethal while only a few individuals from the two others survive. Analysis of relations :between phenotypes and genotypes strongly suggests that the major phenotypic alterations observed do not result from inactivation of the HMG-I/Y gene. (C) 2004 Elsevier SAS. All rights reserved.