Genome-Wide Identification and Analysis of the EPF Gene Family in Sorghum bicolor (L.) Moench

Abstract

The EPIDERMAL PATTERNING FACTOR (EPF) plays a crucial role in plant response to abiotic stress. While the EPF has been extensively studied in model plants such as Arabidopsis thaliana, there is a lack of research on identifying EPF genes in the whole sorghum genome and its response to drought stress. In this study, we employed bioinformatics tools to identify 12 EPF members in sorghum. Phylogenetic tree analysis revealed that SbEPFs can be categorized into four branches. Further examination of the gene structure and protein conservation motifs of EPF family members demonstrated the high conservation of the SbEPF sequence. The promoter region of SbEPFs was found to encompass cis-elements responsive to stress and plant hormones. Moreover, real-time fluorescence quantitative results indicated that the SbEPFs have a tissue-specific expression. Under drought stress treatment, most SbEPF members were significantly up-regulated, indicating their potential role in drought response. Our research findings establish a foundation for investigating the function of SbEPFs and offer candidate genes for stress-resistant breeding and enhanced production in sorghum.

Keywords: EPIDERMAL PATTERNING FACTOR (EPF); Sorghum bicolor (L.) Moench; bioinformatics; drought stress.

Figure 1

Multiple alignment of the C-terminal region between SbEPF protein sequences. Parentheses, number of omitted amino acid residues; *, conserved cysteine residues; blue line, predicted pairs of cysteine residue forming disulfide bonds.

Figure 2

Chromosomal localization of SbEPF family in Sorghum. Size of each chromosome and gene position can be estimated according to the scale on the left of the figure. Chromosome colors represent gene abundance.

Figure 3

Phylogenetic analysis of EPF family genes in P. trichocarpa, Zea mays, Picea abies, Oryza sativa, Amborella trichopoda, and Arabidopsis thaliana. Different species are indicated by different colors.

Figure 4

Gene structure and conserved protein motifs analysis of members in SbEPF family. (A) Gene structures of SbEPFs. (B) Conserved motifs of SbEPFs.

Figure 5

Logo analysis of EPF family conserved domain in (A) Sorghum (B) Rice and (C) Arabidopsis. The overall height of each stack indicates the sequence conservation at that point. The height of each letter (representing a residue) shows the relative frequency of the corresponding residue at that position.

Figure 6

Analysis of cis-acting elements of promoter of EPF family gene in Sorghum. (A) Number of SbEPF prompter containing cis-acting elements. (B) The occurrences frequency of each cis-acting element in the promoter region of each category. The colors in the grid represent the number of cis-acting element.

Figure 7

Tissue-specific expression profiles of SbEPF family. (A) Expression level of SbEPFs in different sorghum tissues (B) Expression level of SbEPFs under drought stress in sorghum (drought stress line: XN1; drought susceptible line: Aihongmao). Different lowercase letters indicated significant differences at 0.05 level.