Premium
Os ORC 3 is required for lateral root development in rice
Author(s) -
Chen Xinai,
Shi Jing,
Hao Xi,
Liu Huili,
Shi Jianghua,
Wu Yunrong,
Wu Zhongchang,
Chen Mingxiu,
Wu Ping,
Mao Chuanzao
Publication year - 2013
Publication title -
the plant journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.058
H-Index - 269
eISSN - 1365-313X
pISSN - 0960-7412
DOI - 10.1111/tpj.12126
Subject(s) - primordium , lateral root , biology , meristem , mutant , microbiology and biotechnology , gene knockdown , arabidopsis thaliana , botany , genetics , arabidopsis , shoot , gene
Summary The origin recognition complex ( ORC ) is a pivotal element in DNA replication, heterochromatin assembly, checkpoint regulation and chromosome assembly. Although the functions of the ORC have been determined in yeast and model animals, they remain largely unknown in the plant kingdom. In this study, O ryza sativa O rigin R ecognition C omplex subunit 3 ( O s ORC 3 ) was cloned using map‐based cloning procedures, and functionally characterized using a rice ( O ryza sativa ) orc3 mutant. The mutant showed a temperature‐dependent defect in lateral root ( LR ) development. Map‐based cloning showed that a G → A mutation in the 9th exon of O s ORC 3 was responsible for the mutant phenotype. O s ORC 3 was strongly expressed in regions of active cell proliferation, including the primary root tip, stem base, lateral root primordium, emerged lateral root primordium, lateral root tip, young shoot, anther and ovary. O s ORC 3 knockdown plants lacked lateral roots and had a dwarf phenotype. The root meristematic zone of ORC 3 knockdown plants exhibited increased cell death and reduced vital activity compared to the wild‐type. CYCB 1;1:: GUS activity and methylene blue staining showed that lateral root primordia initiated normally in the orc3 mutant, but stopped growing before formation of the stele and ground tissue. Our results indicate that O s ORC 3 plays a crucial role in the emergence of lateral root primordia.