|LOPEZ-ARREDONDO, DAMAR - Texas Tech University|
|ODILON OJEDA-RIVERA, JONATHAN - Texas Tech University|
|HERRERA-ESTRELLA, LUIS - Texas Tech University|
Submitted to: National Center for Biotechnology Information (NCBI)
Publication Type: Other
Publication Acceptance Date: 12/9/2021
Publication Date: 4/10/2022
Citation: Ulloa, M., Lopez-Arredondo, D., Odilon Ojeda-Rivera, J., Payton, P.R., Herrera-Estrella, L. 2022. Cotton (Gossypium hirsutum L.) root transcriptional response to the southern Root-Knot Nematode (RKN) Meloidogyne incognita infestation. National Center for Biotechnology Information (NCBI).
Technical Abstract: Root transcript profiles from 3 conventional heirloom cotton (Gossypium hirsutum) were compared as an initial step to identify differentially expressed genes in response to infested with southern root-knot nematode (Meloidogyne incognita; RKN) infestation. The RKN-susceptible cultivar Acala SJ-2 (SJ2) was compared to the moderately resistant Upland Wild Mexico Jack Jones (WMJJ) and RKN-resistant Acala NemX. These cultivars have been shown to be useful genetic models for detecting and introgressing RKN resistance genes into commercial Upland cotton. A total of 18 libraries were prepared for next-generation RNA sequence profiling on roots 10 and 23 days after inoculation with RKN in addition to non-infested control roots. RNA-seq quantification was performed using kallisto version 0.46.1. The G. hirsutum TM-1 UTx v2.1 genome was used as a reference genome to align the reads. Annotated contigs or transcripts revealed that the RKN-resistant cultivar NemX did not activate major gene expression changes in response to RKN infestation and suggested that RKN-resistance is promoted by a constitutive primed-like state of defense genes. Gene ontology and protein homology analyses indicate that the NemX root transcriptional landscape is enriched genes related to jasmonic and salicylic acid, two key phytohormones involved in plant defense responses. Additionally, the expression of cotton genes coding for disease resistance and receptor proteins linked to RKN-resistance and perception in plants was up-regulated in NemX roots, compared to susceptible SJ2 and WMJJ roots. Further, gene sequences coding for TIR-NBL-LRR R proteins, previously identified as candidate genes for RKN-resistance, were over-expressed in NemX roots. These genes belong to chromosomes Chr. A11 and its homeolog Chr. D11, in which RKN quantitative trait loci (QTLs) for resistance were previously reported. These data provide novel insights into the molecular mechanisms that underlie RKN resistance in cotton and members of detected gene families located in the confidence interval of a previously identified QTL associated with RKN resistance represent promising candidates that might facilitate the development of molecular markers that can be employed to efficiently introduce pest/pathogen resistance into commercial cotton cultivars.