Conservation of Lotus and Arabidopsis Basic Helix-Loop-Helix Proteins Reveals New Players in Root Hair Development
Conservation of Lotus and Arabidopsis Basic Helix-Loop-Helix Proteins Reveals New Players in Root Hair Development
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DOI：
10.1104/pp.109.143867
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发表时间：
2009-11-01
期刊：
影响因子：
7.4
通讯作者：
Szczyglowski, Krzysztof
中科院分区：
文献类型：
--
作者：
Karas, Bogumil;Amyot, Lisa;Szczyglowski, Krzysztof
碱性螺旋-环-螺旋（bHLH）蛋白是植物转录调控因子的一个大家族。虽然它们已被证明在各种各样的发育过程中发挥重要作用，但相对较少的功能特征。在此，我们描述了Lotus japonicus ROOTHAIRLESS1 （LjRHL1）位点的图谱克隆。该位点的有害突变阻止了根毛的发育，这也使固氮细菌对寄主根的定植流产。我们发现LjRHL1基因编码一种假定的bHLH转录因子，该转录因子以非冗余的方式控制日本蓟根毛的发育。同源性搜索和跨物种互补实验确定拟南芥bHLH蛋白家族的三个成员At2g24260、At4g30980和At5g58010与LjRHL1功能等同。奇怪的是，At2g24260和At4g30980 mRNA物种的积累独立于已知的根毛细胞命运的正调节因子，而这三个基因都以部分冗余的方式调节拟南芥的根毛发育。
Basic helix-loop-helix (bHLH) proteins constitute a large family of transcriptional regulators in plants. Although they have been shown to play important roles in a wide variety of developmental processes, relatively few have been functionally characterized. Here, we describe the map-based cloning of the Lotus japonicus ROOTHAIRLESS1 (LjRHL1) locus. Deleterious mutations in this locus prevent root hair development, which also aborts root hair-dependent colonization of the host root by nitrogen-fixing bacteria. We show that the LjRHL1 gene encodes a presumed bHLH transcription factor that functions in a nonredundant manner to control root hair development in L. japonicus. Homology search and cross-species complementation experiments defined three members of the Arabidopsis (Arabidopsis thaliana) bHLH protein family, At2g24260, At4g30980, and At5g58010, as functionally equivalent to LjRHL1. Curiously, At2g24260 and At4g30980 mRNA species accumulate independently from the known positive regulators of root hair cell fate, while all three genes act in a partially redundant manner to regulate root hair development in Arabidopsis.