Identification and expression analysis of the PbrMLO gene family in pear, and functional verification of PbrMLO23

doi:10.1016/S2095-3119(20)63558-4

摘要/Abstract

摘要：

本研究共鉴定到了24个PbrMLO基因，并将其分为5个亚家族(I，II，III，IV，V)，全基因组重复和分散重复促进了PbrMLO家族的扩大。此外，基因表达分析显示PbrMLO基因分布在梨的不同组织中，表明其功能不同。我们选择PbrMLO23进行进一步的功能分析。qRT-PCR表达谱分析显示PbrMLO23在花粉中有高表达。亚细胞定位分析显示PbrMLO23位于细胞膜上。当反义寡核苷酸降低PbrMLO23基因的表达量时，花粉管长度变长，说明PbrMLO23具有抑制花粉管生长的功能作用。综上所述，这些结果提供了对PbrMLO基因家族及其功能特征的深刻认识，为进一步分析PbrMLO在梨中的功能奠定了基础。

Abstract:

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.

Key words: MLO , pear , gene expression , pollen tube

. [J]. Journal of Integrative Agriculture, 2021, 20(9): 2410-2423.

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

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