Evolutionary and molecular analysis of Dof transcription factors identified a conserved motif for intercellular protein trafficking
Evolutionary and molecular analysis of Dof transcription factors identified a conserved motif for intercellular protein trafficking
复制标题
DOI：
10.1111/nph.12223
复制
发表时间：
2013-06-01
期刊：
影响因子：
9.4
通讯作者：
Kim, Jae-Yean
中科院分区：
文献类型：
--
作者：
Chen, Huan;Ahmad, Munawar;Kim, Jae-Yean
转录因子在植物细胞间的运输在植物发育过程中起着重要的调控作用，但细胞自主转录因子和非细胞自主转录因子之间的进化关系尚不清楚。AtDof4.1，命名为细胞间运输DOF 1（ITD 1），被选为代表NCA成员，以探索这种进化关系。利用结构域功能分析和交换研究，我们研究了植物特异性Dof TF家族成员在拟南芥和其他物种中的细胞间运输。我们确定了一个保守的细胞间运输基序（ITM），这是必要的和足够的选择性细胞到细胞的贩运，并可以赋予获得功能的细胞到细胞的运动能力，否则细胞自主TF。令人惊讶的是，来自植物界Dof成员的相关基序的功能扩展到了缺乏胞间连丝的单细胞植物。相比之下，与NCA KNOX同源结构域相关的藻类同源结构域要么效率低下，要么不能赋予这种细胞间运动功能。Dof ITM似乎早于植物界中选择性胞间连丝运输的进化，这很可能充当了Dof蛋白作为NCA TF进化的分子模板。然而，在早期非维管植物的进化过程中，可能已经获得了有效的交通KNOX同源域（HD）蛋白的能力。
Cell-to-cell trafficking of transcription factors (TFs) has been shown to play an important role in the regulation of plant developmental events, but the evolutionary relationship between cell-autonomous and noncell-autonomous (NCA) TFs remains elusive. AtDof4.1, named INTERCELLULAR TRAFFICKING DOF 1 (ITD1), was chosen as a representative NCA member to explore this evolutionary relationship. Using domain structurefunction analyses and swapping studies, we examined the cell-to-cell trafficking of plant-specific Dof TF family members across Arabidopsis and other species. We identified a conserved intercellular trafficking motif (ITM) that is necessary and sufficient for selective cell-to-cell trafficking and can impart gain-of-function cell-to-cell movement capacity to an otherwise cell-autonomous TF. The functionality of related motifs from Dof members across the plant kingdom extended, surprisingly, to a unicellular alga that lacked plasmodesmata. By contrast, the algal homeodomain related to the NCA KNOX homeodomain was either inefficient or unable to impart such cell-to-cell movement function. The Dof ITM appears to predate the evolution of selective plasmodesmal trafficking in the plant kingdom, which may well have acted as a molecular template for the evolution of Dof proteins as NCA TFs. However, the ability to efficiently traffic for KNOX homeodomain (HD) proteins may have been acquired during the evolution of early nonvascular plants.