title: A maize ADP-ribosylation factor ZmArf2 increases organ and seed size by promoting cell expansion in Arabidopsis.
abstract: ADP-ribosylation factors (ARFs) are small GTP-binding proteins that regulate a wide variety of cell functions. Previously, we isolated a new ARF, ZmArf2, from maize (Zea mays). Sequence and expression characteristics indicated that ZmArf2 might play a critical role in the early stages of endosperm development. In this study, we investigated ZmArf2 function by analysis of its GTP-binding activity and subcellular localization. We also over-expressed ZmArf2 in Arabidopsis and measured organ and cell size and counted cell numbers. The expression levels of five organ size-associated genes were also determined in 35S::ZmArf2 transgenic and wild-type plants. Results showed that the recombinant ZmArf2 protein purified from Escherichia coli exhibited GTP-binding activity. Subcellular localization revealed that ZmArf2 was localized in the cytoplasm and plasma membrane. ZmArf2 over-expression in Arabidopsis showed that 35S::ZmArf2 transgenic plants were taller and had larger leaves and seeds compared to wild-type plants, which resulted from cell expansions, not an increase in cell numbers. In addition, three cell expansion-related genes, AtEXP3, AtEXP5 and AtEXP10, were upregulated in 35S::ZmArf2 transgenic lines, while the expression levels of AtGIF1 and AtGRF5, were unchanged. Collectively, our studies suggest that ZmArf2 has an active GTP-binding function, and plays a crucial role in growth and development in Arabidopsis through cell expansion mediated by cell expansion genes.
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Qilei
authors.initials: Q
authors.lastname: Wang
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Xue
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Yuling
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Dong
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Long
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Deng
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Zhiyan
authors.initials: Z
authors.lastname: Ma
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Dahe
authors.initials: D
authors.lastname: Qiao
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Chunhui
authors.initials: C
authors.lastname: Hu
authors.affiliation: College of Agriculture, Henan Agricultural University, Collaborative Innovation Center of Henan Grain Crops, National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, China.
authors.forename: Yangliu
authors.initials: Y
authors.lastname: Ren
mesh_terms: D020727:ADP-Ribosylation Factors / Q000235:genetics* / Q000378:metabolism; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000254:growth & development*; D049108:Cell Enlargement; D002462:Cell Membrane / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D018515:Plant Leaves / Q000166:cytology / Q000235:genetics / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D012639:Seeds / Q000166:cytology / Q000235:genetics / Q000254:growth & development*; D015854:Up-Regulation; D003313:Zea mays / Q000235:genetics*
chemical_list: D010940:Plant Proteins; D020727:ADP-Ribosylation Factors