Open Access

ARTICLE

Molecular Basis of Unique Branching Phenotypes in Salvia splendens and the Role of PSY

by Peipei Hong^1,#, Mei Wang^2,#, Liting Zhi², Hongwei Chen^2,3,4,*, Kefeng Liu¹, Hongli Wang²

1 College of Humanities and Urban-Rural Development, Beijing University ofAgriculture, Beijing, 102206, China
2 College of Landscape Architecture, Beijing University of Agriculture, Beijing, 102206, China
3 Beijing Collaborative Innovation Center for Eco-Environmental Improvement with Forestry and Fruit Trees, Beijing, 102206, China
4 Beijing Engineering Research Center of Rural Landscape Planning and Design, Beijing, 102206, China

* Corresponding Author: Hongwei Chen. Email:
# Co-first author

(This article belongs to the Special Issue: Plant Omics in Challenging Environment)

Phyton-International Journal of Experimental Botany 2022, 91(6), 1211-1226. https://doi.org/10.32604/phyton.2022.018435

Received 24 July 2021; Accepted 29 November 2021; Issue published 14 February 2022

Abstract

The branching system of higher plants plays a very important role in plant morphogenesis, and the number of branches can directly affect crop yield and the ornamental value of plants. It is a complicated development process involving complex molecular mechanisms. The ‘Cailinghong’ variety of Salvia splendens is characterized by its great branching ability with the ability to grow into a spherical form naturally, without pinching. To gain insight into the molecular events during the branching development of S. splendens, suppressive subtractive hybridization (SSH) technology was used to screen differentially expressed genes between the erect plant type (strain 35) and the spherical plant type (‘Cailinghong’). In total, 96 and 116 unigenes were annotated. Four and eight unigenes up-regulated in ‘Cailinghong’ and strain 35, respectively, were associated with plant hormone anabolism and signal transduction, suggesting that they participate in the branching process. One of these genes, phytoene synthase (PSY), is a precursor of the new plant hormone group strigolactones. Using the PSY fragment (192 bp) as a template, the cDNA sequence of PSY in S. splendens was cloned and named SsPSY. A relative expression analysis and transgenic test results indicated that SsPSY plays an important role in lateral branch development in ‘Cailinghong’. These results provide new insight into the molecular mechanisms underlying branching in S. splendens.

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Keywords

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