A novel allele of Mitogen Activated Protein Kinase 6 is linked to disease resistance and constitutive immunity in rice.
Authors: C.G., G., Mohammed, J., Rao, D., Gaur, N., Supriyo, A. R., Sao, N., Niranjan, D., Tiwari, S., Laha, G. S., Barbadikar, K. M., Sundaram, R. M., Maganti, S. M., Patel, H. K., Sonti, R. V.
An induced mutant line of the rice cultivar Samba Mahsuri shows broad-spectrum resistance to bacterial blight, linked to a novel missense SNP (S84P) in the OsMAPK6 gene on chromosome 6. Multi-omics analyses indicate that this mutation confers constitutive immunity, likely through reduced brassinosteroid signaling, offering a new resistance allele for rice breeding.
The study identified a major QTL (qDTH3) on chromosome 3 responsible for a 7‑10‑day earlier heading phenotype in the rice line SM93, using QTL‑seq, KASP genotyping, association mapping, and transcriptomic analysis to fine‑map the locus to a 2.53 Mb region and pinpoint candidate genes. SNP markers linked to these genes were proposed as tools for breeding early‑maturing, climate‑resilient rice varieties.
The study performed integrative small RNA sequencing and transcriptomic profiling across ten anther developmental stages of Kitaake rice to map sRNA‑related gene expression and phasiRNA production. It uncovered previously undescribed post‑meiotic 21‑nt and 24‑nt phasiRNA loci with distinct accumulation patterns and nucleotide compositions, suggesting diverse biogenesis mechanisms and specialized roles in pollen development.