Isolation and Amino Acid Sequence of Two New PR-4 Proteins from Wheat

Abstract

We have purified and characterized two new pathogenesis-related (PR) proteins from wheat belonging to the PR-4 family. We named the proteins wheatwin3 and wheatwin4 in analogy with the previously characterized wheatwin1 and wheatwin2. Their isoelectric points were 7.1 and 8.4, respectively. We determined the complete amino acid sequence of both proteins by a rapid approach based on the knowledge of the primary structures of the homologous wheatwin1 and wheatwin2. Wheatwin3 differs from wheatwin1 in one substitution at position 88, while wheatwin4 differs from wheatwin2 in one substitution at position 78. The secondary structure and solvent accessibility of these residues were determined on the three-dimensional model of wheatwinl. Residue 88 was very accessible and was located in a flexible region. Preliminary results indicate that, like wheatwin1 and wheatwin2, wheatwin3 and wheatwin4 have antifungal activity.

Molecular Insights into the Role of Cysteine-Rich Peptides in Induced Resistance to Fusarium oxysporum Infection in Tomato Based on Transcriptome Profiling

“…The proteins of the family are divided into two main classes. Class II proteins include tobacco PR-4a, which is induced by TMV infection, a barley seed protein called barwin [ 57 ], and wheatwin 1-4 isolated from wheat [ 58 , 59 ]. The genes of wheat PR-4 proteins have been cloned and shown to be selectively induced by pathogens, inducers of SAR, and wounding [ 60 ].…”

Structural and Functional Characterization of PR-4 SUGARWINs From Sugarcaneand Their Role in Plant Defense

“…In many plant species, homologs of the BARWIN protein are associated with the plant response to fungal infection and mechanical wounding (Linthorst et al, 1991; Hejgaard et al, 1992; Caruso et al, 1999; Agrawal et al, 2003; Bravo et al, 2003; Li et al, 2010; Souza et al, 2017). In addition to SUGARWIN, antifungal activity has been ascribed to BARWIN-like proteins found in barley (Hejgaard et al, 1992), W. japonica (Kiba et al, 2003), wheat (Caruso et al, 2001), maize (Bravo et al, 2003), rice (Zhu et al, 2006), apple (Bai et al, 2013), and cacao (Menezes et al, 2014).…”

Wheat pathogenesis‐related proteins of class 4 have ribonuclease activity

“…Up to now, although their effect in inhibiting the pathogen hyphal growth and spore germination has been reported [3], their action mechanism and interaction with pathogen molecular targets are still unknown. In the last years, we have isolated and sequenced four PR4 proteins from wheat kernels, named wheatwin1 to wheatwin4, that inhibit phytopathogenic fungi with a wide host range (e.g., Botrytis cinerea ) and host specific pathogens (e.g., Fusarium culmorum , F. graminearum ) [3–5]. We demonstrated that wheatwin1 and wheatwin2 and their genes are specifically induced in wheat seedlings infected with Fusarium culmorum and upon treatment with systemic acquired resistance activators [6,7]; the cDNAs have been cloned and the recombinant proteins expressed in E. coli [8,9].…”