Overexpression of the maize GRF10, an endogenous truncated growth-regulating factor protein, leads to reduction in leaf size and plant height.
It has long been thought that growth-regulating factors (GRFs) gene family members act as transcriptional activators to play important roles in multiple plant developmental processes. However, the recent characterization of Arabidopsis GRF7 showed that it functions as a transcriptional repressor of osmotic stress-responsive genes. This highlights the complex and diverse mechanisms by which different GRF members use to take action. In this study, the maize (Zea mays L.) GRF10 was functionally characterized to improve this concept. The deduced ZmGRF10 protein retains the N-terminal QLQ and WRC domains, the characteristic regions as protein-interacting and DNA-binding domains, respectively. However, it lacks nearly the entire C-terminal domain, the regions executing transactivation activity. Consistently, ZmGRF10 protein maintains the ability to interact with GRF-interacting factors (GIFs) proteins, but lacks transactivation activity. Overexpression of ZmGRF10 in maize led to a reduction in leaf size and plant height through decreasing cell proliferation, whereas the yield-related traits were not affected. Transcriptome analysis revealed that multiple biological pathways were affected by ZmGRF10 overexpression, including a few transcriptional regulatory genes, which have been demonstrated to have important roles in controlling plant growth and development. We propose that ZmGRF10 aids in fine-tuning the homeostasis of the GRF-GIF complex in the regulation of cell proliferation.
National Maize Improvement Center of China, Key Laboratory of Maize Biology and Genetic Breeding of Ministry of Agriculture, China Agricultural University, Beijing, 100193, China.
Lei
L
Wu
Dengfeng
D
Zhang
Ming
M
Xue
Jianjun
J
Qian
Yan
Y
He
Shoucai
S
Wang
D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D006824:Hybridization, Genetic; D008954:Models, Biological; D009929:Organ Size / Q000235:genetics; D010641:Phenotype; D010937:Plant Growth Regulators / Q000378:metabolism*; D018515:Plant Leaves / Q000033:anatomy & histology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D019655:Quantitative Trait, Heritable; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D015533:Transcriptional Activation; D059467:Transcriptome / Q000235:genetics; D003313:Zea mays / Q000033:anatomy & histology* / Q000235:genetics*
D010937:Plant Growth Regulators; D010940:Plant Proteins
GIF; RNA-Seq; growth-regulating factor; maize; overexpression; transcriptional activator