A single nucleotide mutation in GID1c disrupts its interaction with DELLA1 and causes a GA-insensitive dwarf phenotype in peach.

Jun Cheng,Tingting Xiong,Xia Ye,Xianbo Zheng,Mengmeng Zhang,Zijing Guo,Jiancan Feng,Yajun Jiang,Wei Wang,Jidong Li,Bin Tan

doi:10.1111/pbi.13094

Jun Cheng, Tingting Xiong + Show 9 more

Open Access

https://doi.org/10.1111/pbi.13094

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Journal: Plant biotechnology journal	Publication Date: Mar 6, 2019
Citations: 54	License type: CC BY 4.0

Affiliation: Henan Agricultural University

Abstract

SummaryPlant stature is one important factor that affects the productivity of peach orchards. However, little is known about the molecular mechanism(s) underlying the dwarf phenotype of peach tree. Here, we report a dwarfing mechanism in the peach cv. FenHuaShouXingTao (FHSXT). The dwarf phenotype of ‘FHSXT’ was caused by shorter cell length compared to the standard cv. QiuMiHong (QMH). ‘FHSXT’ contained higher endogenous GA levels than did ‘QMH’ and did not response to exogenous GA treatment (internode elongation). These results indicated that ‘FHSXT’ is a GA‐insensitive dwarf mutant. A dwarf phenotype‐related single nucleotide mutation in the gibberellic acid receptor GID1 was identified in ‘FHSXT’ (GID1c S191F), which was also cosegregated with dwarf phenotype in 30 tested cultivars. GID1cS191F was unable to interact with the growth‐repressor DELLA1 even in the presence of GA. ‘FHSXT’ accumulated a higher level of DELLA1, the degradation of which is normally induced by its interaction with GID1. The DELLA1 protein level was almost undetectable in ‘QMH’, but not reduced in ‘FHSXT’ after GA 3 treatment. Our results suggested that a nonsynonymous single nucleotide mutation in GID1c disrupts its interaction with DELLA1 resulting in a GA‐insensitive dwarf phenotype in peach.

Highlights

The cultivation of dwarf fruit trees is widely used in modern production of many fruits, such as apple, sweet cherry and peach, since it reduces the length of the juvenile period, results in higher quality and yield and allows for efficient mechanized management (Lang et al, 2001; Smolka et al, 2010)
The peach genome contains two GID1 genes (GID1b and GID1c) and GID1c was significantly up-regulated in ‘FHSXT’ compared to ‘QMH’ (Figure 3d). These results suggested that the changes in transcript level of genes involved in Gibberellic acids (GAs) synthesis and signalling were not the reason for the dwarf phenotype of ‘FHSXT’
After 3 h of GA treatment, the DELLA1 protein in ‘QMH’ was difficult to detect, but the DELLA1 protein in ‘FHSXT’ was not degraded compared with control. These results strongly suggested that the DELLA1 protein was degraded in ‘QMH’ in response to GA3 treatment

Summary

Introduction

The cultivation of dwarf fruit trees is widely used in modern production of many fruits, such as apple, sweet cherry and peach, since it reduces the length of the juvenile period, results in higher quality and yield and allows for efficient mechanized management (Lang et al, 2001; Smolka et al, 2010). Horticultural practices such as pruning and spraying growth retardant are usually used to constrain tree growth, which is costly in terms of materials, time and labour. With the rapid development of genome-editing techniques, creating dwarfed cultivars through genetic modification may prove more efficient than traditional breeding technology. Research on the underlying mechanisms that yield smaller statured peach trees will be helpful for breeding peach cultivars suitable to dwarfed culture

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