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Journal of Integrative Agriculture  2022, Vol. 21 Issue (5): 1332-1345    DOI: 10.1016/S2095-3119(21)63768-1
Special Issue: 园艺-分子生物合辑Horticulture — Genetics · Breeding
Horticulture Advanced Online Publication | Current Issue | Archive | Adv Search |
Genome-wide identification of WOX gene family in apple and a functional analysis of MdWOX4b during adventitious root formation
XU Xiao-zhao1, CHE Qin-qin1, 3, CHENG Chen-xia1, 2, YUAN Yong-bing1, 3, WANG Yong-zhang1
1 College of Horticulture, Qingdao Agricultural University, Qingdao 266109, P.R.China
2 Qingdao Key Laboratory of Genetic Development and Breeding in Horticultural Plants, Qingdao Agricultural University, Qingdao 266109, P.R.China
3 Qingdao Key Laboratory of Modern Agriculture Quality and Safety Engineering, Qingdao Agricultural University, Qingdao 266109, P.R.China
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Abstract  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.  
Keywords:  WOX gene       apple        adventitious root        rootstock  
Received: 23 December 2020   Accepted: 10 June 2021
Fund: This research was funded by the National Natural Science Foundation of China (31801824), the Breeding Plan of Shandong Provincial Qingchuang Research Team, China (2019), and the Scientific Research Funds for High-level Personnel of Qingdao Agricultural University, China (663/1118036 and 663/1119046).  We appreciate the linguistic assistance provided by TopEdit (
About author:  XU Xiao-zhao, E-mail:; Correspondence WANG Yong-zhang, E-mail:

Cite this article: 

XU Xiao-zhao, CHE Qin-qin, CHENG Chen-xia, YUAN Yong-bing, WANG Yong-zhang. 2022. Genome-wide identification of WOX gene family in apple and a functional analysis of MdWOX4b during adventitious root formation. Journal of Integrative Agriculture, 21(5): 1332-1345.

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