Journal of Proteomics & Bioinformatics
Open Access

Abstract

Quantitative phosphoproteomics of sweet orange (Citrus sinensis) infected by Candidatus Liberibacter

Daniel Chen, Qijie Guan, Bryan Cao and Sixue Chen*

Huanglongbing (HLB or Citrus Greening Disease) is a destructive citrus disease that has impacted the U.S. citrus industry as well as global citrus industry for many years. There is yet to be a practical cure for HLB. Currently, there are only temporary and costly solutions of applying insecticides to target the psyllid vector and burning down the infected trees. Here we investigated the protein and phosphoprotein differences between control (healthy) and diseased citrus leaves to identify potential biomarkers essential towards fighting HLB within the trees themselves. Proteins were extracted from control and diseased leaves, followed by trypsin digestion, phosphopeptide enrichment and label-free quantitative proteomics. In total, we identified 1539 proteins and 278 phosphoproteins, among which 63 proteins and 23 phosphoproteins exhibited significant changes between control and diseased samples. Proteins in response to stimulus were increased at both total protein level and phosphorylation level. Interestingly, proteins related to membranes and complexes were decreased, but increased at phosphorylation level. Several differential phosphoproteins (e.g., a nuclear pore complex protein and a glutathione-S-transferase) could play important roles in battling the devastating disease HLB, one that we can hopefully conquer in the near future.

Published Date: 2021-02-16; Received Date: 2021-01-26