Main content area

Ectopic expression of the maize ZmADF3 gene in Arabidopsis revealing its functions in kernel development

Qiao, Dahe, Dong, Yongbin, Zhang, Long, Zhou, Qiang, Hu, Chunhui, Ren, Yangliu, Li, Yuling
Plant cell, tissue, and organ culture 2016 v.126 no.2 pp. 239-253
Arabidopsis, RNA, Western blotting, amino acids, developmental stages, gene expression regulation, gene overexpression, genes, microfilament proteins, open reading frames, phylogeny, popcorn, quantitative polymerase chain reaction, regulatory sequences, screening, seed development, seeds, sequence analysis, tissues, transgenic plants, two hybrid system techniques
Actin-depolymerizing factors (ADFs) are the members of actin-binding proteins, which play pivotal roles in various cellular processes in plant cells. In this study, we isolated an ADF gene ZmADF3 from the kernels of a popcorn inbred N04. This gene had a 417 bp open reading frame (ORF) which encoded for 139 amino acids. Phylogenetic analysis showed that ZmADF3 had a high sequence identity with TaADF3 and OsADF4. Quantitative real-time PCR and western blotting showed that ZmADF3 expressed variously according to tissues and developmental stages during kernel development both in RNA and in protein levels. A 1738 bp promoter for ZmADF3 was obtained and the cis-acting regulatory elements were predicted. Furthermore, yeast two-hybrid screening revealed that ZmADF3 interacted with glyceradehyde-3-phosphate dehydrogenase (GAPDH). Heterologous overexpression of ZmADF3 showed an increase in seed size in transgenic Arabidopsis plants mainly through the increase in cell size. In addition, the positive regulation of seed size genes SHB1 and IKU1 were up-regulated while the negative regulators AP2 and ARF2 were down-regulated in the transgenic lines. Our results showed that ZmADF3 might play important roles in kernel development in maize. However, further research should be done to thoroughly explore the mechanism of ZmADF3 in playing these functions.