Rice zinc finger protein DST enhances grain production through controlling Gn1a/OsCKX2 expression

The phytohormone cytokinin (CK) positively regulates the activity and function of the shoot apical meristem (SAM), which is a major parameter determining seed production. The rice (Oryza sativa L.) Gn1a / OsCKX2 (Grain number 1a / Cytokinin oxidase 2) gene, which encodes a cytokinin oxidase, has bee...

Full description

Saved in:
Bibliographic Details
Published in:Proceedings of the National Academy of Sciences - PNAS 2013-02, Vol.110 (8), p.3167-3172
Main Authors: Li, Shuyu, Zhao, Bingran, Yuan, Dingyang, Duan, Meijuan, Qian, Qian, Tang, Li, Wang, Bao, Liu, Xiaoqiang, Zhang, Jie, Wang, Jun, Sun, Jiaqiang, Liu, Zhao, Feng, Yu-Qi, Yuan, Longping, Li, Chuanyou
Format: Article
Language:English
Subjects:
Agricultural production
Alleles
Amino Acid Sequence
Biological Sciences
Cloning, Molecular
Crops, Agricultural
Cytokinins
Enzymes
Gene expression
Gene expression regulation
Genes
Genetic mutation
Grains
Meristems
Molecular Sequence Data
Mutation
Oryza - physiology
Panicles
Plant Proteins - chemistry
Plant Proteins - genetics
Plant Proteins - physiology
Plants
Proteins
Rice
Sequence Homology, Amino Acid
Zinc Fingers
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The phytohormone cytokinin (CK) positively regulates the activity and function of the shoot apical meristem (SAM), which is a major parameter determining seed production. The rice (Oryza sativa L.) Gn1a / OsCKX2 (Grain number 1a / Cytokinin oxidase 2) gene, which encodes a cytokinin oxidase, has been identified as a major quantitative trait locus contributing to grain number improvement in rice breeding practice. However, the molecular mechanism of how the expression of OsCKX2 is regulated in planta remains elusive. Here, we report that the zinc finger transcription factor DROUGHT AND SALT TOLERANCE (DST) directly regulates OsCKX2 expression in the reproductive meristem. DST-directed expression of OsCKX2 regulates CK accumulation in the SAM and, therefore, controls the number of the reproductive organs. We identify that DST ʳᵉᵍ¹, a semidominant allele of the DST gene, perturbs DST-directed regulation of OsCKX2 expression and elevates CK levels in the reproductive SAM, leading to increased meristem activity, enhanced panicle branching, and a consequent increase of grain number. Importantly, the DST ʳᵉᵍ¹ allele provides an approach to pyramid the Gn1a -dependent and Gn1a -independent effects on grain production. Our study reveals that, as a unique regulator of reproductive meristem activity, DST may be explored to facilitate the genetic enhancement of grain production in rice and other small grain cereals.
ISSN:0027-8424
1091-6490
DOI:10.1073/pnas.1300359110