Genome-Wide Identification and Expression Profiling Analysis of WOX Family Protein-Encoded Genes in Triticeae Species

• Main Authors: Lei Shi, Ke Wang, Lipu Du, Yuxia Song, Huihui Li, Xingguo Ye
• Format: Article
• Language: English
• Published: MDPI AG 2021-08-01
• Series: International Journal of Molecular Sciences
• Subjects: Triticeae species; WUSCHEL-related homeobox; chromosomal location; phylogenetic analysis; differential expression
• Online Access: https://www.mdpi.com/1422-0067/22/17/9325
• ISSN: 1661-6596; 1422-0067

The WOX family is a group of plant-specific transcription factors which regulate plant growth and development, cell division and differentiation. From the available genome sequence databases of nine Triticeae species, 199 putative <i>WOX</i> genes were identified. Most of the identified <i>WOX</i> genes were distributed on the chromosomes of homeologous groups 1 to 5 and originated via the orthologous evolution approach. Parts of <i>WOX</i> genes in <i>Triticum aestivum</i> were confirmed by the specific PCR markers using a set of <i>T</i><i>riticum. durum</i>-<i>T</i><i>. aestivum</i> genome D substitution lines. All of these identified WOX proteins could be grouped into three clades, similar to those in rice and <i>Arabidopsis</i>. WOX family members were conserved among these Triticeae plants; all of them contained the HOX DNA-binding homeodomain, and WUS clade members contained the characteristic WUS-box motif, while only WUS and WOX9 contained the EAR motif. The RNA-seq and qPCR analysis revealed that the <i>TaWOX</i> genes had tissue-specific expression feature. From the expression patterns of <i>TaWOX</i> genes during immature embryo callus production, <i>TaWOX9</i> is likely closely related with the regulation of regeneration process in <i>T</i><i>. aestivum</i>. The findings in this study could provide a basis for evolution and functional investigation and practical application of the WOX family genes in Triticeae species.