Gene amplification followed by functional diversification is a major force in evolution. A typical example of this is seen in the WUSCHEL-RELATED HOMEOBOX （WOX） gene family, named after the Arabidopsis stem cell reg...Gene amplification followed by functional diversification is a major force in evolution. A typical example of this is seen in the WUSCHEL-RELATED HOMEOBOX （WOX） gene family, named after the Arabidopsis stem cell regulator WUSCHEL. Here we analyze functional divergence in the WOX gene family. Members of the WUS clade, except the cambium stem cell regulator WOX4, can substitute for WUS function in shoot and floral stem cell maintenance to different degrees. Stem cell function of WUS requires a canonical WUS-box, essential for interaction with TPL/TPR co-repressors, whereas the repressive EAR domain is dispensable and the acidic domain seems only to be required for female fertility. In contrast to the WUS clade, members of the ancient WOX13 and the WOX9 clades cannot support stem cell maintenance. Although the homeodomains are interchangeable between WUS and WOX9 clade members, a WUS- compatible homeodomain together with canonical WUS-box is not sufficient for stem cell maintenance. Our results suggest that WOX function in shoot and floral meristems of Arabidopsis is restricted to the modern WUS clade, suggesting that stem cell control is a derived function. Yet undiscovered functional domains in addition to the homeodomain and the WUS-box are necessary for this function.展开更多
The plant-specific WUSCHEL-related homeobox(WOX)genes are crucial for plant growth and development.Here,we systematically identified the MdWOX gene family in apple at the genome-wide level,and analyzed the phylogeneti...The plant-specific WUSCHEL-related homeobox(WOX)genes are crucial for plant growth and development.Here,we systematically identified the MdWOX gene family in apple at the genome-wide level,and analyzed the phylogenetic relationships,conserved motifs,gene structure,and syntenic relationships of the MdWOX genes.A total of 18 MdWOX genes were identified and phylogenetic analysis placed them into three clades.The phylogenetic relationships among the WOXs were further supported by the analyses of gene structure and conserved motifs.Chromosomal distribution and synteny analysis revealed that whole-genome and segmental duplications have played key roles in MdWOX gene family expansion.Moreover,the MdWOX genes exhibit tissue-specific expression patterns and MdWOX4a,MdWOX4b,MdWOX5b,MdWOX11/12a,and MdWOX11/12b may play essential roles in adventitious root development.The adventitious rooting ability was enhanced in MdWOX4b transgenic tobacco lines.The results of this study provide useful information for future functional studies on MdWOXs in the development of apple rootstocks.展开更多
文摘Gene amplification followed by functional diversification is a major force in evolution. A typical example of this is seen in the WUSCHEL-RELATED HOMEOBOX （WOX） gene family, named after the Arabidopsis stem cell regulator WUSCHEL. Here we analyze functional divergence in the WOX gene family. Members of the WUS clade, except the cambium stem cell regulator WOX4, can substitute for WUS function in shoot and floral stem cell maintenance to different degrees. Stem cell function of WUS requires a canonical WUS-box, essential for interaction with TPL/TPR co-repressors, whereas the repressive EAR domain is dispensable and the acidic domain seems only to be required for female fertility. In contrast to the WUS clade, members of the ancient WOX13 and the WOX9 clades cannot support stem cell maintenance. Although the homeodomains are interchangeable between WUS and WOX9 clade members, a WUS- compatible homeodomain together with canonical WUS-box is not sufficient for stem cell maintenance. Our results suggest that WOX function in shoot and floral meristems of Arabidopsis is restricted to the modern WUS clade, suggesting that stem cell control is a derived function. Yet undiscovered functional domains in addition to the homeodomain and the WUS-box are necessary for this function.
基金funded by the National Natural Science Foundation of China(31801824)the Breeding Plan of Shandong Provincial Qingchuang Research Team,China(2019)the Scientific Research Funds for Highlevel Personnel of Qingdao Agricultural University,China(663/1118036 and 663/1119046)。
文摘The plant-specific WUSCHEL-related homeobox(WOX)genes are crucial for plant growth and development.Here,we systematically identified the MdWOX gene family in apple at the genome-wide level,and analyzed the phylogenetic relationships,conserved motifs,gene structure,and syntenic relationships of the MdWOX genes.A total of 18 MdWOX genes were identified and phylogenetic analysis placed them into three clades.The phylogenetic relationships among the WOXs were further supported by the analyses of gene structure and conserved motifs.Chromosomal distribution and synteny analysis revealed that whole-genome and segmental duplications have played key roles in MdWOX gene family expansion.Moreover,the MdWOX genes exhibit tissue-specific expression patterns and MdWOX4a,MdWOX4b,MdWOX5b,MdWOX11/12a,and MdWOX11/12b may play essential roles in adventitious root development.The adventitious rooting ability was enhanced in MdWOX4b transgenic tobacco lines.The results of this study provide useful information for future functional studies on MdWOXs in the development of apple rootstocks.
