Genome-wide identification, phylogeny and expression analysis of the SBP-box gene family in maize(Zea mays)

The SQUAMOSA promoter binding protein(SBP)-box genes encode a kind of plant-specific transcription factors(TFs) and play important roles in the regulation of plant development. In this study, a genome-wide characterization of this family was conducted in maize(Zea mays). Thirty-one SBP-box genes were i dentified to be di stributed in nine chromosomes an d 16 of the m were complementary to the mature Zmmi R156 sequences. All the Z. mays SBP(Zm S BP) genes were classified into two clusters with eight subgroups according to the phylogenetic analysis of proteins, which were consistent with the pattern of exon-intron structures. The phylogenetic tree of the Zm SBP, Oryz a sativa SBP-like(Os SPL) and Arabidopsis thaliana SBP-like(AtSPL) genes were constructed and all the SBP-box genes were divided into eight groups, which was the same as the classification of Zm SBP genes. The comparision of the expression profiles of all SBP-box genes in these three species indicated that most orthologous genes had similar expression patterns. The results from this study provided a basic understanding of the Zm SBP genes and might facilitate future researches for elucidating the SBP-box genes function in maize.