Open AccessOverexpression of a tomato miR171 target gene Sl GRAS 24 impacts multiple agronomical traits via regulating gibberellin and auxin homeostasis
Author(s) -
Huang Wei,
Peng Shiyuan,
Xian Zhiqiang,
Lin Dongbo,
Hu Guojian,
Yang Lu,
Ren Maozhi,
Li Zhengguo
Publication year - 2017
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.12646
Subject(s) - biology , gibberellin , auxin , solanum , arabidopsis , gene , meristem , pollen , phenotype , anthesis , microbiology and biotechnology , transcription factor , transcriptome , genetically modified tomato , transgene , botany , genetics , genetically modified crops , gene expression , mutant , cultivar
Summary In Arabidopsis , the miR171‐ GRAS module has been clarified as key player in meristem maintenance. However, the knowledge about its role in fruit crops like tomato ( Solanum lycopersicum ) remains scarce. We previously identified tomato Sl GRAS 24 as a target gene of Sly‐miR171 . To study the role of this probable transcription factor, we generated transgenic tomato plants underexpressing Sl GRAS 24 , overexpressing Sl GRAS 24 , overexpressing Sly‐miR171 and expressing β‐glucuronidase ( GUS ) under the Sl GRAS 24 promoter (pro Sl GRAS 24 ‐ GUS ). Plants overexpressing Sl GRAS 24 ( Sl GRAS 24 ‐ OE ) had pleiotropic phenotypes associated with multiple agronomical traits including plant height, flowering time, leaf architecture, lateral branch number, root length, fruit set and development. Many GA /auxin‐related genes were down‐regulated and altered responsiveness to exogenous IAA / NAA or GA 3 application was observed in Sl GRAS 24 ‐ OE seedlings. Moreover, compromised fruit set and development in Sl GRAS 24 ‐ OE was also observed. These newly identified phenotypes for Sl GRAS 24 homologs in tomato were later proved to be caused by impaired pollen sacs and fewer viable pollen grains. At anthesis, the comparative transcriptome results showed altered expression of genes involved in pollen development and hormone signalling. Taken together, our data demonstrate that Sl GRAS 24 participates in a series of developmental processes through modulating gibberellin and auxin signalling, which sheds new light on the involvement of hormone crosstalk in tomato development.