A proteomic analysis of grain yield-related traits in wheat.

Sintayehu D Daba,Xiaoqin Liu,Mohsen Mohammadi,Uma Aryal,Abdelbagi Ismail

doi:10.1093/aobpla/plaa042

Abstract

Grain yield, which is mainly contributed by tillering capacity as well as kernel number and weight, is the most important trait to plant breeders and agronomists. Label-free quantitative proteomics was used to analyse yield-contributing organs in wheat. These were leaf sample, tiller initiation, spike initiation, ovary and three successive kernel development stages at 5, 10 and 15 days after anthesis (DAA). We identified 3182 proteins across all samples. The largest number was obtained for spike initiation (1673), while the smallest was kernel sample at 15 DAA (709). Of the 3182 proteins, 296 of them were common to all seven organs. Organ-specific proteins ranged from 148 in ovary to 561 in spike initiation. When relative protein abundances were compared to that of leaf sample, 347 and 519 proteins were identified as differentially abundant in tiller initiation and spike initiation, respectively. When compared with ovary, 81, 35 and 96 proteins were identified as differentially abundant in kernels sampled at 5, 10 and 15 DAA, respectively. Our study indicated that two Argonaute proteins were solely expressed in spike initiation. Of the four expansin proteins detected, three of them were mainly expressed during the first 10 days of kernel development after anthesis. We also detected cell wall invertases and sucrose and starch synthases mainly during the kernel development period. The manipulation of these proteins could lead to increases in tillers, kernels per spike or final grain weight, and is worth exploring in future studies.

Highlights

Wheat contributes to nearly one-fifth of the total dietary calories and protein worldwide (Shiferaw et al 2010; Reynolds et al 2012)
The OV and the subsequent three kernel development samples (5, 10 and 15 days after anthesis (DAA)) provide enrichment of proteins that are abundant during kernel formation and progression towards developmental stages, and, critical for determination of kernel size and weight
We studied these yield forming organs via label-free LC-mass spectrometry (MS)/MS-based proteome quantification according to schematic proteomic workflow presented in Fig. 3 to identify and quantify the intensity of proteins for each sample

Summary

Introduction

Wheat contributes to nearly one-fifth of the total dietary calories and protein worldwide (Shiferaw et al 2010; Reynolds et al 2012). Genetic gains, defined as yield increases per unit time, have recently slowed down to

Methods

Results

Discussion

Conclusion