Analysis of the Basic Characteristics and Expression Patterns of the 4CL,C4H and PAL Gene Families in Eucommia Ulmoides

LIU Huanlong; CHEN Shuming; XIN Feng

doi:10.3969/j.issn.1003-4749.2025.05.002

Abstract：Chlorogenic acid is one of the main active components in Eucommia ulmoides,and 4CL,C4H and PAL are the key genes for the synthesis of chlorogenic acid.In order to study the basic characteristics and expression patterns of the 4CL,C4H and PAL gene families in Eucommia ulmoides,the members of Eu4CL,EuC4H and EuPAL gene families in Eucommia ulmoides were identified by bioinformatics methods,and their physicochemical properties,chromosome location,phylogenetic tree,gene structure,conserved motifs,Cis-elements in the promoter region and expression patterns of Eu4CL,EuC4H and EuPAL genes in different tissues of Eucommia ulmoides and leaves of Eucommia ulmoides strains with different contents of chlorogenic acid were analyzed.The results showed that a total of seven members of the 4CL gene family,two members of the C4H gene family and five members of the PAL gene family were identified in the Eucommia ulmoides genome.The analysis of physicochemical properties showed that the amino acid length,relative molecular mass,isoelectric point and average hydrophilic value of Eu4CL,EuC4H and EuPAL proteins were different to varying degrees.The analysis of chromosome location showed that the Eu4CL,EuC4H and EuPAL gene families were distributed on nine chromosomes of Eucommia ulmoides.The analysis of phylogenetic tree showed that the Eu4CL,EuC4H and EuPAL gene families had high homology with Populus trichocarpa and Arabidopsis thaliana.The analysis of gene structure showed that the Eu4CL gene family had 4 to 6 introns,the EuC4H gene family had 1 to 2 introns,and the EuPAL gene family had only one intron.The analysis of conserved motif showed that the Eu4CL,EuC4H and EuPAL gene families all contained Motif1 to Motif9,which were highly conserved.The analysis of Cis-elements in the promoter region showed that there were a large number of Cis-elements involved in environmental stress response,plant hormone response and WRKY,MYB,bHLH transcription factor binding sites in the promoter region of Eu4CL,EuC4H and EuPAL gene family.The expression pattern analysis showed that the expression levels of Eu4CL,EuC4H and EuPAL genes in different tissues of Eucommia ulmoides were different and had obvious tissue specificity.Among them,Eu4CL3,EuC4H1,EuPAL3 and EuPAL5 had higher expression levels in leaves,and Eu4CL7,EuC4H1,EuPAL3 and EuPAL4 had higher expression levels in xylem.In addition,the expression levels of Eu4CL3,EuPAL1 and EuPAL5 in the leaves of Eucommia ulmoides with high chlorogenic acid content were higher than those of Eucommia ulmoides with low chlorogenic acid content.This study aimed to understand the basic characteristics and expression patterns of PAL,C4H and 4CL gene families in Eucommia ulmoides,and to provide reference for the breeding of Eucommia ulmoides strains with high chlorogenic acid content.