Proteome-Wide Analysis of Lysine 2-Hydroxyisobutyrylated Proteins in Fusarium oxysporum

Front Microbiol. 2021 Feb 10:12:623735. doi: 10.3389/fmicb.2021.623735. eCollection 2021.

Abstract

Protein lysine 2-hydroxyisobutyrylation (K hib ), a new type of post-translational modification, occurs in histones and non-histone proteins and plays an important role in almost all aspects of both eukaryotic and prokaryotic living cells. Fusarium oxysporum, a soil-borne fungal pathogen, can cause disease in more than 150 plants. However, little is currently known about the functions of K hib in this plant pathogenic fungus. Here, we report a systematic analysis of 2-hydroxyisobutyrylated proteins in F. oxysporum. In this study, 3782 K hib sites in 1299 proteins were identified in F. oxysporum. The bioinformatics analysis showed that 2-hydroxyisobutyrylated proteins are involved in different biological processes and functions and are located in diverse subcellular localizations. The enrichment analysis revealed that K hib participates in a variety of pathways, including the ribosome, oxidative phosphorylation, and proteasome pathways. The protein interaction network analysis showed that 2-hydroxyisobutyrylated protein complexes are involved in diverse interactions. Notably, several 2-hydroxyisobutyrylated proteins, including three kinds of protein kinases, were involved in the virulence or conidiation of F. oxysporum, suggesting that K hib plays regulatory roles in pathogenesis. Moreover, our study shows that there are different K hib levels of F. oxysporum in conidial and mycelial stages. These findings provide evidence of K hib in F. oxysporum, an important filamentous plant pathogenic fungus, and serve as a resource for further exploration of the potential functions of K hib in Fusarium species and other filamentous pathogenic fungi.

Keywords: Fusarium oxysporum; lysine 2-hydroxyisobutyrylation; post-translational modification; proteomics; virulence.