AXR4 is required for localization of the auxin influx facilitator AUX1
AXR4 is required for localization of the auxin influx facilitator AUX1
复制标题
DOI：
10.1126/science.1122847
复制
发表时间：
2006-05-26
期刊：
影响因子：
56.9
通讯作者：
Estelle, M.
中科院分区：
文献类型：
--
作者：
Dharmasiri, S.;Swarup, R.;Estelle, M.
AUX1和PIN生长素内流和外排促进剂是根生长发育的关键调节因子。为了使根向重力性发生，AUX1和PIN2必须通过侧根帽将生长素运输到伸长的表皮细胞。遗传学研究表明，AXR4的功能与AUX1的功能相同。在这里，我们证明了AXR4是一种以前未知的内质网(ER)辅助蛋白，它调节AUX1的定位，而不是PIN蛋白的定位。AXR4的缺失导致AUX1在表皮细胞的内质网中异常积累，这表明AXR4的无性表型是由AUX1在根表皮中的缺陷运输引起的。
The AUX1 and PIN auxin influx and efflux facilitators are key regulators of root growth and development. For root gravitropism to occur, AUX1 and PIN2 must transport auxin via the lateral root cap to elongating epidermal cells. Genetic studies suggest that AXR4 functions in the same pathway as AUX1. Here we show that AXR4 is a previously unidentified accessory protein of the endoplasmic reticulum (ER) that regulates localization of AUX1 but not of PIN proteins. Loss of AXR4 resulted in abnormal accumulation of AUX1 in the ER of epidermal cells, indicating that the axr4 agravitropic phenotype is caused by defective AUX1 trafficking in the root epidermis.