Adventitious root formation in rice requires OsGNOM1 and is mediated by the OsPINs family

在谷物的含纤维的根系统包括首先偶然根(艺术) ，它在营养素和水举起起重要作用。关于位于 AR 开发下面的分子的机制的当前的知识仍然是有限的。我们这里报导四米饭(Oryza sativa L.) 的隔离异种从不同基因背景，所有哪个在 AR 是有缺点的形成。这些异种展出了侧面的根(LR ) 和 gravitropism 的部分损失的减少的数字。也显示的异种提高了敏感到 N-1-naphthylphthalamic 酸，极的植物生长素运输的一个禁止者(轻拍) ，显示变化影响了植物生长素运输。用四异种之一的位置的克隆表明它被一个 guanine 核苷酸交换因素的 loss-of-function 为 ADP-ribosylation 因素(OsGNOM1 ) 引起。转基因的植物显示出的 promoter::GUS 的 RT-PCR 和分析那 OsGNOM1 在 AR primordia，脉管的纸巾， LR，根尖端，叶子，花药和词根静脉被表示，与类似于植物生长素的一个分发模式。另外， OsPIN2， OsPIN5b 和 OsPIN9 的表情在异种被改变。一起拿，这些调查结果显示 OsGNOM1 通过调整影响艺术的形成轻拍。

The fibrous root system in cereals comprises primarily adventitious roots （ARs）, which play important roles in nutrient and water uptake. Current knowledge regarding the molecular mechanism underlying AR development is still limited. We report here the isolation of four rice （Oryza sativa L.） mutants, from different genetic backgrounds, all of which were defective in AR formation. These mutants exhibited reduced numbers of lateral roots （LRs） and partial loss of gravitropism. The mutants also displayed enhanced sensitivity to N-l-naphthylphthalamic acid, an inhibitor of polar auxin transport （PAT）, indicating that the mutations affected auxin transport. Positional cloning using one of the four mutants revealed that it was caused by loss-of-function of a guanine nucleotide exchange factor for ADP- ribosylation factor （OsGNOM1）. RT-PCR and analysis of promoter：：GUS transgenic plants showed that OsGNOM1 is expressed in AR primordia, vascular tissues, LRs, root tips, leaves, anthers and lemma veins, with a distribution pattern similar to that of auxin. In addition, the expressions of OsPIN2, OsPIN5b and OsPIN9 were altered in the mutants. Taken together, these findings indicate that OsGNOM1 affects the formation of ARs through regulating PAT.