Screening and Identification of Cinnamoyl CoA Reductase Genes Associated with Lignin Synthesis and Abiotic Stress in Boehmeria nivea

ABSTRACT

Ramie (Boehmeria nivea (L.) Gaudich.) is a bast fiber crop that can be used in textiles, medicine, and feed and for environmental protection. Lignin plays an important role in plant defense and development, but lignin is a critical factor affecting the fiber and feed quality of ramie. Cinnamoyl-CoA reductase (CCR) is a pivotal enzyme in plant lignin biosynthesis that catalyzes the synthesis of these common precursors. Here, eight CCR genes of ramie were identified based on sequence characteristics, gene structure, phylogenetic relationships, stress response to abiotic treatment, and the correlation of lignin and flavonoid contents with the expression level of genes. The eight CCR genes were cloned and divided into three groups with significant differences in their structures and sequence characteristics. BnCCR1 and BnCCR5 are involved in lignin biosynthesis. BnCCR4 plays a role in defense-related processes. It is worth noting that BnCCR2 is different from the structure and function of typical CCR, which is closely related to the synthesis of both lignin and flavonoids, and may play different roles in the xylem and phloem of ramie. The functions of the other genes require further investigation. These findings provide a basis for subsequent functional verification of CCR genes using genetic engineering.

摘要

苎麻是一种韧皮纤维作物，可用于纺织、医药、饲料和环境保护. 木质素在植物防御和发育中起着重要作用，但木质素是影响苎麻纤维和饲料品质的关键因素. 肉桂酰辅酶a还原酶（CCR）是植物木质素生物合成的关键酶，催化这些常见前体的合成. 根据序列特征、基因结构、系统发育关系、对非生物处理的胁迫反应以及木质素和类黄酮含量与基因表达水平的相关性，鉴定和克隆了8个苎麻CCR基因，并将其分为三组，在结构和序列特征上存在显著差. BnCCR1和BnCCR5参与木质素的生物合成. BnCCR4在防御相关过程中发挥作用. 值得注意的是，BnCCR2不同于典型CCR的结构和功能，后者与木质素和黄酮类化合物的合成密切相关，可能在苎麻的木质部和韧皮部中发挥不同的作用. 其他基因的功能需要进一步研究. 这些发现为随后使用基因工程对CCR基因进行功能验证提供了基础.

KEYWORDS:

• Cinnamoyl CoA reductase (CCR)
• Boehmeria nivea
• gene expression
• abiotic stress
• lignin
• flavonoid

摘要:

• 肉桂酰辅酶A还原酶（CCR）
• 基因表达
• 非生物胁迫
• 木质素
• 类黄酮

Acknowledgements

We acknowledge everyone who contributed to this article.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/15440478.2023.2257901

Additional information

Funding

This work was supported by grants from the National Natural Science Foundation of China (31301374), Natural Science Foundation of Hunan Province, China (2021JJ40378), the Doctoral Science Launch Project of Hunan University of Arts and Science, China (19BSQD35), the Central Public- interest Scientific Institution Basal Research Fund (Y2023PT11) and Agricultural Science, Technology Innovation Program (ASTIP) of CAAS (2023IBFC).