Isolation and identification of two new alleles of STICHEL in Arabidopsis
Isolation and identification of two new alleles of STICHEL in Arabidopsis
复制标题
拟南芥STICHEL两个新等位基因的分离鉴定
DOI：
10.1016/j.bbrc.2018.03.197
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发表时间：
2018
影响因子：
3.1
通讯作者：
An Lijun
中科院分区：
文献类型：
--
作者：
Xi Ali;Yang Xuying;Deng Meng;Chen Yu;Shao Jingxia;Zhao Jun;An Lijun
植物毛状体因其独特的生长特性，长期以来一直被选为研究细胞发育调控机制的模式系统。为了探索有助于毛状体发育的新成分，我们在拟南芥中进行了大规模的正向遗传筛选，发现了两个具有显著毛状体分枝缺陷的隐性突变体，这两个突变体都显示了一个分枝毛状体。经过图位克隆和遗传互补实验，我们证实它们是Stichel(STI)的新等位基因，STI被认为是毛发分支的关键调节基因。STI基因的预测产物由三个功能结构域组成，中间有一个与真细菌DNA聚合酶III g亚基序列相似的大结构域，N端有两个PEST结构域，N端和C端分别有两个核定位信号(NLS)。我们的生化和分子分析表明，末端的一个PEST结构域可能对STI调节毛状体分支的功能起重要作用。它可以直接与细胞形状和内复制的重要连接物BRACHLESS毛状体(BLT)相互作用。由于先前的数据表明，STI在调节毛状体分支中的功能与DNA复制和肌动蛋白或微管细胞骨架结构无关，我们对STI和BLT之间直接相互作用结构域的发现掩盖了STI在细胞形态发生中的可能作用。
Plant trichome has long been selected as a model system to study the regulatory mechanism during cell.development due to its unique growth characteristics. In an effort to explore new components that.contribute to trichome development, we performed large-scale forward genetic screening in Arabidopsis,.and found two recessive mutants with significant trichome branching defects, both of which display one.branched trichomes. After map-based cloning, genetic complementation experiments, we confirmed.that they are new alleles of STICHEL (STI) that has been reported to act as a key regulator of trichome.branching. The predicted product of STI gene is comprised by three functional domains including a large.domain with sequence similarity to eubacterial DNA polymerase III g-subunit in the middle, two PEST.domains in the N terminal, and two nuclear localization signals (NLS) at the very N terminal and C.terminal, respectively. Our biochemistry and molecular analysis indicated that a PEST domain in the Nterminal.could be important for STI functioning in regulating trichome branching. It can directly interact.with BRACHLESS TRICHOME (BLT), an important linker of cell shape and endoreplication. Because the.previously data showed that the function of STI in regulating trichome branching was not linked to DNA.replication and actin or microtubule cytoskeleton configuration, our findings of the direct interaction.domains between STI and BLT veiled the probable roles of STI in cell morphogenesis.