来自中国华中农业大学的科学家从水稻中分离出了一个可以控制不定根生长发育的关键调节因子基因WOX11，水稻根系主要由大量的不定根及其侧根组成，但是人们对水稻根系性状遗传规律的认识和了解比较缺乏。
课题组负责人周道绣发现的WOX11基因通过介导植物生长素和细胞分裂素的信号传导来调控水稻不定根的生长发育。（生物谷Bioon.com）
生物谷推荐原始出处：
The Plant Cell March 3, 2009; 10.1105/tpc.108.061655
The WUSCHEL-Related Homeobox Gene WOX11 Is Required to Activate Shoot-Borne Crown Root Development in Rice
Yu Zhao 1, Yongfeng Hu 1, Mingqiu Dai 1, Limin Huang 1, and Dao-Xiu Zhou 2*
1 National Key Laboratory for Crop Genetic Improvement, Huazhong Agricultural University, 430070 Wuhan, China
2 Institut de Biotechnologie des Plantes, Université Paris Sud 11, 91405 Orsay, France
In rice (Oryza sativa), the shoot-borne crown roots are the major root type and are initiated at lower stem nodes as part of normal plant development. However, the regulatory mechanism of crown root development is poorly understood. In this work, we show that a WUSCHEL-related Homeobox (WOX) gene, WOX11, is involved in the activation of crown root emergence and growth. WOX11 was found to be expressed in emerging crown roots and later in cell division regions of the root meristem. The expression could be induced by exogenous auxin or cytokinin. Loss-of-function mutation or downregulation of the gene reduced the number and the growth rate of crown roots, whereas overexpression of the gene induced precocious crown root growth and dramatically increased the root biomass by producing crown roots at the upper stem nodes and the base of florets. The expressions of auxin- and cytokinin-responsive genes were affected in WOX11 overexpression and RNA interference transgenic plants. Further analysis showed that WOX11 directly repressed RR2, a type-A cytokinin-responsive regulator gene that was found to be expressed in crown root primordia. The results suggest that WOX11 may be an integrator of auxin and cytokinin signaling that feeds into RR2 to regulate cell proliferation during crown root development.
