Overexpression of oHIOMT results in various morphological, anatomical, physiological and molecular changes in switchgrass

Bibliographic Details
Title: Overexpression of oHIOMT results in various morphological, anatomical, physiological and molecular changes in switchgrass
Authors: Yanhua Huang, Xianzhi Lai, Changfa Liu, Wentao Zhu, Yongren Hao, Zehui Zheng, Kai Guo
Source: Frontiers in Plant Science, Vol 15 (2024)
Publisher Information: Frontiers Media S.A., 2024.
Publication Year: 2024
Collection: LCC:Plant culture
Subject Terms: HIOMT, melatonin, concentration-dependent, photosynthesis, salt tolerance, lignin content, Plant culture, SB1-1110
More Details: IntroductionMelatonin (N-acetyl-5-methoxytryptamine) is a molecule implicated in multiple biological functions, but exerts contrasting effects on plants owing to concentration differences. Hydroxyindole O-methyltransferase (HIOMT), which catalyzes the last step of melatonin synthesis, plays a crucial role in this context.MethodsTransgenic switchgrass overexpressing oHIOMT with different melatonin levels displayed distinct morphological changes in a concentration-dependent manner. In this study, we divided the transgenic switchgrass into two groups: melatonin-moderate transgenic (MMT) plants and melatonin-rich transgenic (MRT) plants. To determine the concentration-dependent effect of melatonin on switchgrass growth and stress resistance, we conducted comparative morphological, physiological, omics and molecular analyses between MMT, MRT and wild-type (WT) plants.ResultsWe found that oHIOMT overexpression, with moderate melatonin levels, was crucial in regulating switchgrass growth through changes in cell size rather than cell number. Moderate levels of melatonin were vital in regulating carbon fixation, stomatal development and chlorophyll metabolism. Regarding salt tolerance, melatonin with moderate levels activated numerous defense (e.g. morphological characteristics, anatomical structure, antioxidant enzymatic properties, non-enzymatic capacity and Na+/K+ homeostasis). Additionally, moderate levels of oHIOMT overexpression were sufficient to increase lignin content and alter monolignol compositions with an increase in the S/G lignin ratio.DiscussionTaken together, oHIOMT overexpression in switchgrass with different melatonin levels resulted in morphological, anatomical, physiological and molecular changes in a concentration-dependent manner, which characterized by stimulation at low doses and inhibition at high doses. Our study presents new ideas and clues for further research on the mechanisms of the concentration-dependent effect of melatonin.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1664-462X
Relation: https://www.frontiersin.org/articles/10.3389/fpls.2024.1379756/full; https://doaj.org/toc/1664-462X
DOI: 10.3389/fpls.2024.1379756
Access URL: https://doaj.org/article/f1547a47f16445688094d67dee9ca388
Accession Number: edsdoj.f1547a47f16445688094d67dee9ca388
Database: Directory of Open Access Journals
More Details
ISSN:1664462X
DOI:10.3389/fpls.2024.1379756
Published in:Frontiers in Plant Science
Language:English