Yuying Wang†, Linhui Guo †, Yujie Zhao, Xueqing Zhao and Zhaohe Yuan2,*. Systematic analysis and expression profiles of the 4‐coumarate:CoA ligase (4CL)
gene family in Pomegranate (Punica granatum L.). Int. J. Mol. Sci. 2022, 23, 3509. https://doi.org/10.3390/ijms23073509
2022年03月23日，南京林业大学林学院苑兆和教授课题组完成的题为“Systematic analysis and expression profiles of the 4-coumarate:CoA ligase (4CL) gene family in pomegranate (Punica granatum L.)（石榴4-香豆酸:辅酶A连接酶基因家族系统分析与表达模式）”研究论文在International Journal of Molecular Sciences (IF=5.924)刊发。
南京林业大学林学院博士研究生汪钰莹为论文第一作者，苑兆和教授为通讯作者。该研究受到了南京林业大学高层次人才科研启动基金（GXL2014070，GXL2018032），江苏省高校优势学科建设工程（PAPD），江苏省自然科学基金青年基金（BK20180768）和国家留学基金委（202108320304）的支持。
文章原文链接：
https://www.mdpi.com/1422-0067/23/7/3509
Abstract: 4‐Coumarate:CoA ligase (4CL, EC6.2.1.12), located at the end of the phenylpropanoid metabolic pathway, regulates the metabolic direction of
phenylpropanoid derivatives and plays a pivotal role in the biosynthesis of flavonoids, lignin, and other secondary metabolites. In order to understand the
molecular characteristics and potential biological functions of the 4CL gene family in the pomegranate, a bioinformatics analysis was carried out on the identified
4CLs. In this study, 12 Pg4CLs were identified in the pomegranate genome, which contained two conserved amino acid domains: AMP‐binding domain Box I
(SSGTTGLPKGV) and Box II (GEICIRG). During the identification, it was found that Pg4CL2 was missing Box II. The gene cloning and sequencing verified
that this partial amino acid deletion was caused by genome sequencing and splicing errors, and the gene cloning results corrected the Pg4CL2 sequence information in the ‘Taishanhong’ genome. According to the phylogenetic tree, Pg4CLs were divided into three subfamilies, and each subfamily had 1, 1, and 10 members,
respectively. Analysis of cis‐acting elements found that all the upstream sequences of Pg4CLs contained at least one phytohormone response element. An RNA‐seq and protein interaction network analysis suggested that Pg4CL5 was highly expressed in different tissues and may participate in lignin synthesis of pomegranate.
The expression of Pg4CL in developing pomegranate fruits was analyzed by quantitative real‐time PCR (qRT‐PCR), and the expression level of Pg4CL2
demonstrated a decreasing trend, similar to the trend of flavonoid content, indicating Pg4CL2 may involve in flavonoid synthesis and pigment accumulation.
Pg4CL3, Pg4CL7, Pg4CL8, and Pg4CL10 were almost not expressed or lowly expressed, the expression level of Pg4CL4 was higher in the later stage of fruit
development, suggesting that Pg4CL4 played a crucial role in fruit ripening. The expression levels of 4CL genes were significantly different in various fruit
development stages. The results laid the foundation for an in‐depth analysis of pomegranate 4CL gene functions.
Keywords: pomegranate; 4‐Coumarate‐CoA ligase (4CL); gene cloning; lignin; flavonoids; phylogenetic analysis
