DRO1 influences root system architecture in Arabidopsis and Prunus species

作者：Guseman Jessica M; Webb Kevin; Srinivasan Chinnathambi; Dardick Chris

来源：Plant Journal, 2017, 89(6): 1093-1105.

DOI：10.1111/tpj.13470

<jats:title>Summary</jats:title><jats:p>Roots provide essential uptake of water and nutrients from the soil, as well as anchorage and stability for the whole plant. Root orientation, or angle, is an important component of the overall architecture and depth of the root system; however, little is known about the genetic control of this trait. Recent reports in <jats:italic>Oryza sativa</jats:italic> (rice) identified a role for <jats:italic><jats:styled-content style="fixed-case">DEEPER ROOTING</jats:styled-content> 1</jats:italic> (<jats:italic><jats:styled-content style="fixed-case">DRO</jats:styled-content>1</jats:italic>) in influencing the orientation of the root system, leading to positive changes in grain yields under water‐limited conditions. Here we found that <jats:italic><jats:styled-content style="fixed-case">DRO</jats:styled-content>1</jats:italic> and <jats:italic><jats:styled-content style="fixed-case">DRO</jats:styled-content>1</jats:italic>‐related genes are present across diverse plant phyla, and fall within the <jats:styled-content style="fixed-case">IGT</jats:styled-content> gene family. The <jats:styled-content style="fixed-case">IGT</jats:styled-content> family also includes <jats:italic><jats:styled-content style="fixed-case">TAC</jats:styled-content>1</jats:italic> and <jats:italic><jats:styled-content style="fixed-case">LAZY</jats:styled-content>1</jats:italic>, which are known to affect the orientation of lateral shoots. Consistent with a potential role in root development, <jats:italic><jats:styled-content style="fixed-case">DRO</jats:styled-content>1</jats:italic> homologs in Arabidopsis and peach showed root‐specific expression. Promoter–reporter constructs revealed that <jats:italic>At<jats:styled-content style="fixed-case">DRO</jats:styled-content>1</jats:italic> is predominantly expressed in both the root vasculature and root tips, in a distinct developmental pattern. Mutation of <jats:italic>At<jats:styled-content style="fixed-case">DRO</jats:styled-content>1</jats:italic> led to more horizontal lateral root angles. Overexpression of <jats:italic>At<jats:styled-content style="fixed-case">DRO</jats:styled-content>1</jats:italic> under a constitutive promoter resulted in steeper lateral root angles, as well as shoot phenotypes including upward leaf curling, shortened siliques and narrow lateral branch angles. A conserved C‐terminal <jats:styled-content style="fixed-case">EAR</jats:styled-content>‐like motif found in <jats:styled-content style="fixed-case">IGT</jats:styled-content> genes was required for these ectopic phenotypes. Overexpression of <jats:italic>Ppe<jats:styled-content style="fixed-case">DRO</jats:styled-content>1</jats:italic> in <jats:italic>Prunus domestica</jats:italic> (plum) led to deeper‐rooting phenotypes. Collectively, these data indicate a potential application for <jats:italic><jats:styled-content style="fixed-case">DRO</jats:styled-content>1</jats:italic>‐related genes to alter root architecture for drought avoidance and improved resource use.</jats:p>

• 出版日期2017-3