Abstract
SPLs are plant-specific transcription factors that play important regulatory roles in plant growth and development. Systematic analysis of the SPL family has been performed in numerous plants, such as Arabidopsis, rice, and Populus. However, no comparative analysis has been performed across different species to examine evolutionary features. In this study, we present a comparative analysis of SPLs in different species. The results showed that 84 SPLs of the four species can be divided into six groups according to phylogeny. We found that most of the SPL-containing regions in maize showed extensive conservation with duplicated regions of rice and sorghum. A gene duplication analysis in maize indicated that ZmSPLs showed a significant excess of segmental duplication. The Ka/Ks analysis indicated that 9 out of 18 duplicated pairs in maize experienced positive selection, while SPL gene pairs of rice and sorghum mainly evolved under purifying selection, suggesting novel evolutionary features for ZmSPLs. The 31 ZmSPLs were further analyzed by describing their gene structure, phylogenetic relationships, chromosomal location, and expression, Among the ZmSPLs, 13 were predicated to be targeted by miR156s and involved in drought stress response. These results provide the foundation for future functional analyses of ZmSPLs.
Highlights
Transcription factors (TFs) are a large class of regulators controling gene expression by activating or repressing target genes at the transcriptional level
Gene structure analysis indicated that the nuclear localization signal (NLS) region partially overlapped with the second Zn-finger located at the C-terminal of the SBP domain
The number of sorghum SPL genes (SPLs) was similar to that in rice and Arabidopsis. These genes were named ZmSPL1–ZmSPL31 and SbSPL1–SbSPL18 according to their order of distribution on the chromosomes (Tables S2, S3)
Summary
Transcription factors (TFs) are a large class of regulators controling gene expression by activating or repressing target genes at the transcriptional level. Increasing evidence indicates that TFs have important roles in the regulating networks of plant growth and development processes (Riechmann et al, 2001). SPLs (SQUAMOSA promoter binding protein-like) comprise a family of plant-specific transcription factors that contain a highly conserved SBP domain consisting of about 76 amino acids (Chen et al, 2010). This domain has been implicated in DNA binding and nuclear localization, and features two zinc-binding sites assembled as Cys-Cys-Cys-His and Cys-Cys-HisCys, respectively (Klein et al, 1996; Yamasaki et al, 2004). Gene structure analysis indicated that the nuclear localization signal (NLS) region partially overlapped with the second Zn-finger located at the C-terminal of the SBP domain.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
