Morpho-physiological integrators, transcriptome and coexpression network analyses signify the novel molecular signatures associated with axillary bud in chrysanthemum

Sagheer Ahmad; Cunquan Yuan; Qingqing Yang; Yujie Yang; Tangren Cheng; Jia Wang; Huitang Pan; Qixiang Zhang

doi:10.1186/s12870-020-02336-0

Morpho-physiological integrators, transcriptome and coexpression network analyses signify the novel molecular signatures associated with axillary bud in chrysanthemum

BMC Plant Biol. 2020 Apr 7;20(1):145. doi: 10.1186/s12870-020-02336-0.

Authors

Sagheer Ahmad¹, Cunquan Yuan¹, Qingqing Yang¹, Yujie Yang¹, Tangren Cheng¹, Jia Wang¹, Huitang Pan¹, Qixiang Zhang^{2

3}

Affiliations

¹ Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China.
² Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China. zqx@bjfu.edu.cn.
³ Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China. zqx@bjfu.edu.cn.

Abstract

Background: Axillary bud is an important agronomic and economic trait in cut chrysanthemum. Bud outgrowth is an intricate process controlled by complex molecular regulatory networks, physio-chemical integrators and environmental stimuli. Temperature is one of the key regulators of bud's fate. However, little is known about the temperature-mediated control of axillary bud at molecular levels in chrysanthemum. A comprehensive study was designed to study the bud outgrowth at normal and elevated temperature in cut chrysanthemum. Leaf morphology, histology, physiological parameters were studied to correlate the leaf activity with bud morphology, sucrose and hormonal regulation and the molecular controllers.

Results: Temperature caused differential bud outgrowth along bud positions. Photosynthetic leaf area, physiological indicators and sucrose utilization were changed considerable due to high temperature. Comparative transcriptome analysis identified a significant proportion of bud position-specific genes.Weighted Gene Co-expression Network Analysis (WGCNA) showed that axillary bud control can be delineated by modules of coexpressed genes; especially, MEtan3, MEgreen2 and MEantiquewhite presented group of genes specific to bud length. A comparative analysis between different bud positions in two temperatures revealed the morpho-physiological traits associated with specific modules. Moreover, the transcriptional regulatory networks were configured to identify key determinants of bud outgrowth. Cell division, organogenesis, accumulation of storage compounds and metabolic changes were prominent during the bud emergence.

Conclusions: RNA-seq data coupled with morpho-physiological integrators from three bud positions at two temperature regimes brings a robust source to understand bud outgrowth status influenced by high temperature in cut chrysanthemum. Our results provide helpful information for elucidating the regulatory mechanism of temperature on axillary bud growth in chrysanthemum.

Keywords: Axillary bud; Chrysanthemum; High temperature; WGCNA.

Publication types

Comparative Study

MeSH terms

Chrysanthemum / growth & development
Chrysanthemum / metabolism*
Chrysanthemum / ultrastructure
Gene Regulatory Networks
Meristem / physiology*
Plant Leaves / metabolism
Plant Leaves / ultrastructure
Temperature
Transcriptome*

Abstract

Publication types

MeSH terms

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