Genome-wide identification and characterization of NBLRR genes in finger millet (Eleusine coracana L.) and their expression in response to Magnaporthe grisea infection

Alexander Balamurugan; Mallana Gowdra Mallikarjuna; Shilpi Bansal; S Chandra Nayaka; Hosahatti Rajashekara; Tara Satyavathi Chellapilla; Ganesan Prakash

doi:10.1186/s12870-024-04743-z

Genome-wide identification and characterization of NBLRR genes in finger millet (Eleusine coracana L.) and their expression in response to Magnaporthe grisea infection

BMC Plant Biol. 2024 Jan 29;24(1):75. doi: 10.1186/s12870-024-04743-z.

Authors

Alexander Balamurugan¹, Mallana Gowdra Mallikarjuna², Shilpi Bansal^{1

3}, S Chandra Nayaka⁴, Hosahatti Rajashekara⁵, Tara Satyavathi Chellapilla⁶, Ganesan Prakash⁷

Affiliations

¹ Division of Plant Pathology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
² Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India. MG.Mallikarjuna@icar.gov.in.
³ Department of Science and Humanities, SRM Institute of Science and Technology, Modinagar, Uttar Pradesh, 201204, India.
⁴ Department of Studies in Applied Botany and Biotechnology, University of Mysore, Mysore, 570005, India.
⁵ ICAR-Vivekananda Institute of Hill Agriculture, Almora, Uttarakhand, 263601, India.
⁶ ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, Telangana, 500 030, India.
⁷ Division of Plant Pathology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India. g.prakash@icar.gov.in.

Abstract

Background: The nucleotide binding site leucine rich repeat (NBLRR) genes significantly regulate defences against phytopathogens in plants. The genome-wide identification and analysis of NBLRR genes have been performed in several species. However, the detailed evolution, structure, expression of NBLRRs and functional response to Magnaporthe grisea are unknown in finger millet (Eleusine coracana (L.) Gaertn.).

Results: The genome-wide scanning of the finger millet genome resulted in 116 NBLRR (EcNBLRRs1-116) encompassing 64 CC-NB-LRR, 47 NB-LRR and 5 CC_R-NB-LRR types. The evolutionary studies among the NBLRRs of five Gramineae species, viz., purple false brome (Brachypodium distachyon (L.) P.Beauv.), finger millet (E. coracana), rice (Oryza sativa L.), sorghum (Sorghum bicolor L. (Moench)) and foxtail millet (Setaria italica (L.) P.Beauv.) showed the evolution of NBLRRs in the ancestral lineage of the target species and subsequent divergence through gene-loss events. The purifying selection (Ka/Ks < 1) shaped the expansions of NBLRRs paralogs in finger millet and orthologs among the target Gramineae species. The promoter sequence analysis showed various stress- and phytohormone-responsive cis-acting elements besides growth and development, indicating their potential role in disease defence and regulatory mechanisms. The expression analysis of 22 EcNBLRRs in the genotypes showing contrasting responses to Magnaporthe grisea infection revealed four and five EcNBLRRs in early and late infection stages, respectively. The six of these nine candidate EcNBLRRs proteins, viz., EcNBLRR21, EcNBLRR26, EcNBLRR30, EcNBLRR45, EcNBLRR55 and EcNBLRR76 showed CC, NB and LRR domains, whereas the EcNBLRR23, EcNBLRR32 and EcNBLRR83 showed NB and LRR somains.

Conclusion: The identification and expression analysis of EcNBLRRs showed the role of EcNBLRR genes in assigning blast resistance in finger millet. These results pave the foundation for in-depth and targeted functional analysis of EcNBLRRs through genome editing and transgenic approaches.

Keywords: Blast, evolution; Expression analysis; Finger millet; Magnaporthe Grisea; NBLRR.

MeSH terms

Binding Sites
Eleusine* / genetics
Genotype
Nucleotides / metabolism
Phylogeny
Pyricularia grisea

Substances

Nucleotides

Abstract

MeSH terms

Substances

Grants and funding