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Journal of Integrative Agriculture  2021, Vol. 20 Issue (9): 2410-2423    DOI: 10.1016/S2095-3119(20)63558-4
Special Issue: 园艺-分子生物合辑Horticulture — Genetics · Breeding
Horticulture Advanced Online Publication | Current Issue | Archive | Adv Search |
Identification and expression analysis of the PbrMLO gene family in pear, and functional verification of PbrMLO23
GUO Bing-bing1, LI Jia-ming1, LIU Xing1, 2, QIAO Xin1, Musana Rwalinda FABRICE1, WANG Peng1, ZHANG Shao-ling1, WU Ju-you
1 Center of Pear Engineering Technology Research/State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P.R.China
2 School of Life Sciences, Nanjing University, Nanjing 210023, P.R.China
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Mildew resistance locus O (MLO) is a plant-specific gene family that plays an important role in the growth and development of plants and their interactions with the environment.  However, the available information on this gene family in pear is limited.  Here, 24 PbrMLO genes were identified and divided into five subfamilies (I, II, III, IV and V).  Whole-genome duplication (WGD) and dispersed duplication contributed to the expansion of the PbrMLO family.  In addition, gene expression analysis revealed that PbrMLO genes were distributed in various pear tissues, suggesting their diverse functions.  We selected PbrMLO23 for further functional analysis.  Expression profile analysis by qRT-PCR showed that PbrMLO23 was highly expressed in pollen.  Subcellular localization analysis showed that PbrMLO23 was located on the plasma membrane.  When the expression level of PbrMLO23 was knocked down by using antisense oligonucleotides, pollen tube lengths increased, indicating that PbrMLO23 plays a functional role in inhibiting pollen tube growth.  In summary, these results provide evolutionary insight into PbrMLO and its functional characteristics and lay a foundation for further analysis of the functions of PbrMLO members in pear.
Keywords:  MLO        pear        gene expression        pollen tube  
Received: 07 April 2020   Accepted:
Fund: This work was supported by the National Natural Science Foundation of China (31772276), the project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions, China, and the China Postdoctoral Science Foundation (2017M620213).
Corresponding Authors:  Correspondence WU Ju-you, Mobile: +86-13913835567, Tel/Fax: +86-25-84396485, E-mail:   
About author:  GUO Bing-bing, E-mail:;

Cite this article: 

GUO Bing-bing, LI Jia-ming, LIU Xing, QIAO Xin, Musana Rwalinda FABRICE, WANG Peng, ZHANG Shao-ling, WU Ju-you. 2021. Identification and expression analysis of the PbrMLO gene family in pear, and functional verification of PbrMLO23. Journal of Integrative Agriculture, 20(9): 2410-2423.

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