The heterologous expression of conserved Glycine max (soybean) mitogen activated protein kinase 3 (MAPK3) paralogs suppresses Meloidogyne incognita parasitism in Gossypium hirsutum (upland cotton)

Authors: Klink, Vincent; ALKHAROUF, NADIM - Towson University; LAWRENCE, KATHERINE - Auburn University; LAWAJU, BISHO - Mississippi State University; SHARMA, K - Mississippi State University; NIRAULA, PRAKASH - Mississippi State University; MCNEECE, BRANT - Mississippi State University

Submitted to: Transgenic Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/17/2022
Publication Date: 6/28/2022
Citation: Klink, V.P., Alkharouf, N.W., Lawrence, K.S., Lawaju, B., Sharma, K., Niraula, P., Mcneece, B.T. 2022. The heterologous expression of conserved Glycine max (soybean) mitogen activated protein kinase 3 (MAPK3) paralogs suppresses Meloidogyne incognita parasitism in Gossypium hirsutum (upland cotton). Transgenic Research. https://doi.org/10.1007/s11248-022-00312-y.
DOI: https://doi.org/10.1007/s11248-022-00312-y

Interpretive Summary: Genes shown previously to be expressed in a root cell undergoing a defense response to a parasitic pathogen have been identified. The genes, when expressed in a variety of that plant that is normally susceptible became resistant to parasitism by that pathogen. Experiments have been run to express that gene in an agricultural crop to determine if the engineering event results in resistance to a different root parasite. The experiments that have expressed those two genes lead to resistance to parasitism by that root pathogen. The expressed genes that function in resistance belong to a family of 20 genes. Bioinformatics analyses have been done to identify those gene families in crops of worldwide importance and those of importance to U.S. agriculture, including sugarbeet (Beta vulgaris). The experiments have led to the identification of genes that function in the defense of plants to pathogens and are present, broadly, in different genomes of agriculturally important crops.

Technical Abstract: Two conserved Glycine max (soybean) mitogen activated protein kinase 3 (MAPK3) paralogs function in defense to the parasitic soybean cyst nematode Heterodera glycines. Gene Ontology analyses of RNA seq data obtained from MAPK3-1-overexpressing (OE) and MAPK3-2-OE roots compared to their control, as well as MAPK3-1-RNA interference (RNAi) and MAPK3-2-RNAi compared to their control, hierarchically orders the induced and suppressed genes, strengthening the hypothesis that their heterologous expression in Gossypium hirsutum (upland cotton) would impair parasitism by the root knot nematode (RKN) Meloidogyne incognita. MAPK3-1 expression (E) in G. hirsutum suppresses M. incognita root galls, egg masses and J2s by 80.32%, 82.37% and 88.21%, respectfully. Unexpectedly, eggs increase by 28.99%, but are inviable. MAPK3-2-E effects are statistically identical. MAPK3-1-E and MAPK3-2-E decreases root growth 1.49-fold and 1.55-fold, respectively. The reproductive factor (RF) for G. max MAPK3-1-E or MAPK3-2-E roots decreases 60.39% and 50.46%, respectively, compared to controls. The results are consistent with upstream pathogen activated molecular pattern (PAMP) triggered immunity (PTI) and effector triggered immunity (ETI) functioning in defense to H. glycines, showcasing the feasibility of the substitution of these components for the function of a plant species' (cotton's) own endogenous, but apparently non-functioning, defense platform. MAPK homologs that may function in defense have been identified in other important crop species for functional analyses.