Shrivastav, A. | bioRxiv Science

bioRxiv2023

Comparative Genomic and Transcriptomic Analysis of Avirulent and Virulent Strains of Fusarium oxysporum f. sp. carthami: Insights into Pathogenesis and Virulence Determinants in Safflower Infections

Vascular wilt disease incited by Fusarium oxysporum f. sp. carthami (Foc) in Safflower poses a significant threat to its production in India. A comprehensive understanding of the molecular underpinning of compatible and incompatible interaction is of extreme economic importance. In the present study, the genome of a virulent (IARI-5175) and a avirulent (F-00845) Foc strain were sequenced and assembled using data generated from Illumina in combination with Nanopore technologies and HiC. Foc genomes were assembled into 88 and 23 scaffolds with an estimated total size of 46 Mb and 42 Mb respectively for IARI-5175 and F-00845 strains. Reference based mapping of Foc genome with F. oxysporum f. sp. lycopersici (Fol) resulted in chromosomal level ordering of genome and simultaneous identification of accessory genome. Additionally, two lineage specific chromosomes were also identified for virulent Foc strain IARI-5175. Genomic comparisons were made on the basis of effectors, CAZymes, secondary metabolites and mycotoxins to understand the global view pathogenicity in Foc. Moreover, the transcriptome of Foc during compatible and incompatible interaction was sequenced and analyzed leading to the identification of differentially regulated genes. Taken together our study laid a solid foundation to explore novel effector genes that play a crucial role in the establishment of disease and can further be used as targets to devise new strategies to curb wilt disease in safflower.

genomics↗

bioRxiv2020

N-myristoyltransferase: Tracing Steps Backwards to Find a Way Forward

N-myristoylation refers to the attachment of a 14-carbon fatty acid onto the N-terminal glycine residue of a target protein. The myristoylation reaction, catalyzed by N-myristoyltrasnferase (NMT), is essential for regulating cellular activities such as signal transduction, proliferation, migration, differentiation, and transformation. Although a considerable amount of research is performed on the overexpression of NMT in pathogenic conditions, a fundamental knowledge gap exists on the evolution of NMT and the functional impact of myristoylation for normal cellular development and functions. We performed evolutionary analyses of the NMT gene and found that most non-vertebrates harbor a single nmt gene and all vertebrates examined harbor two genes; nmt1 and nmt2. For the first time, we report that teleosts harbor two copies of nmt1, named nmt1a and nmt1b. We traced the evolutionary history of the chromosomal fragments hosting NMT1 and NMT2 in humans and found that NMT1 and NMT2 trace back to a single vertebrate ancestral chromosome. We also report the presence of putative nuclear localization sequence (NLS) and amino acid residues flanking NLS. The presence of phosphorylatable amino acid residues flanking the NLS suggests that nuclear localization of NMT is regulated by phosphorylation. The nuclear localization of NMT suggest its potential role in gene transcription.

evolutionary biology↗