The Arabidopsis proteins AtNHR2A and AtNHR2B are multifunctional proteins integrating plant immunity with other biological processes

Authors: SINGH, RAKSHA; LIYANAGE, ROHANA - UNIVERSITY OF ARKANSAS; GUPTA, CHIRAG - UNIVERSITY OF ARKANSAS; LAY, JACKSON - UNIVERSITY OF ARKANSAS; PEREIRA, ANDY - UNIVERSITY OF ARKANSAS; ROJAS, CLEMENCIA - UNIVERSITY OF ARKANSAS

Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/14/2020
Publication Date: 2/29/2020
Citation: Singh, R., Liyanage, R., Gupta, C., Lay, J.O., Pereira, A., Rojas, C.M. 2020. The Arabidopsis proteins AtNHR2A and AtNHR2B are multifunctional proteins integrating plant immunity with other biological processes. Frontiers in Plant Science. 11:232. https://doi.org/10.3389/fpls.2020.00232.
DOI: https://doi.org/10.3389/fpls.2020.00232

Interpretive Summary: Nonhost resistance is a plant defense that confers resistance to all members of a plant species against a pathogen species, even though this pathogen is able to infect closely related plants and consequently, can be harnessed to generate disease resistant plants. In spite of its importance, nonhost resistance is still poorly understood. We previously identified two Arabidopsis thaliana proteins that are essential for nonhost resistance. The results from this study showed that the two proteins interact with a plethora of proteins of diverse function and are located in multiple cellular compartments, highlighting that these proteins are multi-functional and highly dynamic. However, their specific function is not yet known. Upon investigation, the data collected supports a model which shows they have specialized, independent functions, but also operate together to provide nonhost resistance in plants. While further analysis must be conducted, the initial data should prove valuable for the plant disease resistance research community.

Technical Abstract: AtNHR2A (Arabidopsis thaliana nonhost resistance 2A) and AtNHR2B (Arabidopsis thaliana nonhost resistance 2B) are two proteins required in nonhost resistance, a broad-spectrum mechanism of plant immunity that protects plants against the majority of potential pathogens. AtNHR2A and AtNHR2B are localized to the cytoplasm, chloroplasts and other subcellular compartments of unknown identity. The multiple localizations of AtNHR2A and AtNHR2B, suggest that they are highly dynamic and versatile proteins likely participating in multiple biological processes. In spite of their importance, their specific functions have not been elucidated. Thus, to aid in the functional characterization of these proteins and identify the biological processes in which these proteins participate, we used immunoprecipitation coupled with mass spectrometry (IP-MS), to identify the proteins interacting with AtNHR2A and AtNHR2B and generate their interactome network. Further analysis of the AtNHR2A- and AtNHR2B-interacting proteins using published empirical information revealed that AtNHR2A and AtNHR2B function is not limited to plant immunity, highlighting that these proteins integrate defense outputs with other biological processes.