Coexpression analysis of a large-scale transcriptome identified a calmodulin-like protein regulating the development of adventitious roots in poplar

Zheng'ang Xiao; Yan Zhang; Meifeng Liu; Chang Zhan; Xiaoqing Yang; Tashbek Nvsvrot; Zhaogui Yan; Nian Wang

doi:10.1093/treephys/tpaa078

Coexpression analysis of a large-scale transcriptome identified a calmodulin-like protein regulating the development of adventitious roots in poplar

Tree Physiol. 2020 Oct 7;40(10):1405-1419. doi: 10.1093/treephys/tpaa078.

Authors

Zheng'ang Xiao¹, Yan Zhang¹, Meifeng Liu¹, Chang Zhan¹, Xiaoqing Yang¹, Tashbek Nvsvrot¹, Zhaogui Yan¹, Nian Wang^{1

2}

Affiliations

¹ Forestry Department, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China.
² Hubei Engineering Technology Research Center for Forestry Information, Huazhong Agricultural University, Wuhan 430070, China.

PMID: 32578840
DOI: 10.1093/treephys/tpaa078

Abstract

Poplars are important woody plants, and the ability to form adventitious roots (ARs) is the key factor for their cultivation because most poplars are propagated by cloning. In previous studies, Ca2+ was confirmed to regulate AR formation in poplar. In this study, wild-type poplar cuttings grown in 1.0 mM Ca2+ solution showed the best visible performance of AR development. Coexpression analysis of a large-scale RNA-Seq transcriptome was conducted to identify Ca2+-related genes that regulate AR development in poplar. A total of 15 coexpression modules (CMs) were identified, and two CMs showed high association with AR development. Functional analysis identified a number of biological pathways, including 'oxidation-reduction process', 'response to biotic stimulus' and 'metabolic process', in tissues of AR development. The Ca2+-related pathway was specifically selected, and its regulation in poplar AR development was predicted. A Ca2+ sensor, PdeCML23-1, which is a member of the calmodulin-like protein (CML) family, was found to promote AR development by phenotypic assay of overexpressed PdeCML23-1 transgenic lines at various growing conditions. By measuring cytosolic Ca2+ in AR tips, PdeCML23-1 seemed to play a role in decreasing cytosolic Ca2+ concentration. Additionally, the expression profiles of some genes and phytohormone indole acetic acid (IAA) were also changed in the overexpressed PdeCML23-1 transgenic lines. According to this study, we were able to provide a global view of gene regulation for poplar AR development. Moreover, we also observed the regulation of cytosolic Ca2+ concentration by PdeCML23-1, and this regulation was involved in AR development in poplar. We also predicted that PdeCML23-1 possibly regulates AR development by modulating IAA content in poplar.

Keywords: Ca2+; adventitious roots; calmodulin-like protein; coexpression analysis; cytosolic Ca2+ concentration; poplars.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Calmodulin / genetics
Gene Expression Regulation, Plant
Plant Growth Regulators
Plant Roots / genetics
Populus* / genetics
Transcriptome*

Substances

Calmodulin
Plant Growth Regulators