Genome-Wide Comparative Analysis of the β-glucosidase Family in Five Rosaceae Species and their Potential Role on Lignification of Stone Cells in Chinese White Pear

Abstract

Background: The β-glucosidase BGLU in the glycoside hydrolase family 1 (GH1) is involved in the sugar metabolism of the plant and plays an important role in maintaining the normal physiological function of the plant. Recent studies had shown that β-glucosidase was involved in plant lignification. The lignification in pear fruit is closely related to the formation of pear stone cells, but the BGLU genes family has not been identified in pears.Result: A total of 343 BGLU genes were identified from five species of Rosaceae (Pyrus bretschneideri, Prunus mume, Malus domestica, Prunus avium, Fragaria vesca). According to phylogenetic analysis, 50 PbBGLUs were divided into 8 groups. 298 syntenic pairs were found in intra- and inter-species collinear analysis of five Rosaceae species, found that pears and apples had more syntenic pairs than pear and the other three Rosaceae species. The Ka/Ks analysis of duplication PbBGLU genes in pear indicated that the main mode of expansion of the PbBGLUs was segmental replication and was mainly affected by purification. qRT-PCR showed that the three gene expression patterns of PbBGLU1, PbBGLU15 and PbBGLU16 were basically consistent with the change trend of pear fruit lignin and stone cell content, and may be involved in lignification and stone cell development of pear fruit. Subcellular localization showed that these three candidate genes were all located on the cell wall.Conclusion: In this study, a genome-wide analysis of BGLU genes in five Rosaceae species was carried out, and three candidate genes related to lignification and stone cell development of pear fruits were identified, which laid the foundation for a deeper understanding of the function of BGLU genes in pear fruits and potential in changing pear fruit quality.

Analysis of the β-Glucosidase Family Reveals Genes Involved in the Lignification of Stone Cells in Chinese White Pear (Pyrus bretschneideri Rehd.)

“…We would like to thank everyone who contributed to this article. This manuscript part of the data has been released as a pre-print at Research Square ( Wang et al, 2020 ).…”