Genome-wide analysis of phenylalanine ammonia-lyase (PAL) gene family in five Rosaceae plants and expression analysis and functional identification of Chinese white pear

Anhui Agricultural University, He Fei, China
DOI
10.7287/peerj.preprints.27815v1
Subject Areas
Agricultural Science, Biotechnology
Keywords
Rosaceae plants, P. bretschneideri, lignin, expression analysis, Phenylalanine ammonia lyase (PAL)
Copyright
© 2019 Li et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Li HG, Wang H, Cheng X, Su QX, Zhao Y, Jiang ST, Jin Q, Lin Y, Cai PY. 2019. Genome-wide analysis of phenylalanine ammonia-lyase (PAL) gene family in five Rosaceae plants and expression analysis and functional identification of Chinese white pear. PeerJ Preprints 7:e27815v1

Abstract

Phenylalanine ammonia lyase (PAL) plays an important role in the biosynthesis of secondary metabolites regulating plant growth response. To date, the evolutionary history of the PAL family in Rosaceae plants remains unclear. In this study, we identified 16 PAL homologous genes in five Rosaceae plants (Pyrus bretschneideri, Fragaria vesca, Prunus mume, Prunus persica, and Malus × domestica). We classified these PAL genes into three categories based on phylogenetic analysis,and all PAL genes were distributed on 13 chromosomes. Subsequently, we track gene replication events and perform sliding window analysis. These results revealed the evolution of PAL genes in five Rosaceae plants. We predicted the promoter of the PbPAL genes by PLANTR CARE online software, and found that the 5'regulatory region of both PbPAL1 and PbPAL3 has at least one AC element motif. The results of qRT-PCR analysis found that PbPAL1 and PbPAL2 were highly expressed in the stem and root , while expression level of PbPAL3 was relatively low in different tissues. The expression of PbPAL1 and PbPAL2 genes increased firstly and then decreased at different developmental periods of pear fruit. Among them, the expression of PbPAL1 reached the highest level 55 days after flower. Three PbPAL genes were induced by abiotic stress to varying degrees. We transfected PbPAL1 and PbPAL2 genes into Arabidopsis thaliana, resulting in lignin content increased significantly and thick cell wall of intervascular fibers and xylem cells. In summary, This study laid a foundation for better understanding the molecular evolution of PAL genes in five Rosaceae plants. Furthermore, the present study revealed the role of PbPAL genes in lignin synthesis, and provided basic data for regulating lignin synthesis and stone cell development of pear.

Author Comment

This is a submission to PeerJ for review.

Supplemental Information

Table S1. Primer sequences used for qRT-PCR and vector construction

DOI: 10.7287/peerj.preprints.27815v1/supp-1

Table S2. Primer sequences contained artificial restriction enzyme sites for Bgl II and Spe I

DOI: 10.7287/peerj.preprints.27815v1/supp-2

Figure S1. Sliding window analysis of PAL duplicated genes

DOI: 10.7287/peerj.preprints.27815v1/supp-3

Sequencing Data

Sequencing Data

DOI: 10.7287/peerj.preprints.27815v1/supp-4

Table S3. GusA nonspecific primers

DOI: 10.7287/peerj.preprints.27815v1/supp-5

Table S4. Numbers of cis-elements in promoter region of PbPALs

DOI: 10.7287/peerj.preprints.27815v1/supp-7