Single Nucleotide Polymorphisms in a Gene for Translation Initiation Factor (eIF4G) of Rice (Oryza sativa) Associated with Resistance to Rice tungro spherical virus

Rice tungro disease (RTD) is a serious constraint to rice production in South and Southeast Asia. RTD is caused by Rice tungro spherical virus (RTSV) and Rice tungro bacilliform virus. Rice cv. Utri Merah is resistant to RTSV. To identify the gene or genes involved in RTSV resistance, the association of genotypic and phenotypic variations for RTSV resistance was examined in backcross populations derived from Utri Merah and rice germplasm with known RTSV resistance. Genetic analysis revealed that resistance to RTSV in Utri Merah was controlled by a single recessive gene (tsv1) mapped within an approximately 200-kb region between 22.05 and 22.25 Mb of chromosome 7. A gene for putative translation initiation factor 4G (eIF4Gtsv1) was found in the tsv1 region. Comparison of eIF4Gtsv1 gene sequences among susceptible and resistant plants suggested the association of RTSV resistance with one of the single nucleotide polymorphism (SNP) sites found in exon 9 of the gene. Examination of the SNP site in the eIF4Gtsv1 gene among various rice plants resistant and susceptible to RTSV corroborated the association of SNP or deletions in codons for Val1060-1061 of the predicted eIF4Gtsv1 with RTSV resistance in rice.

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Multilocus Sequence Typing and Single Nucleotide Polymorphism Analysis in Tilletia indica Isolates Inciting Karnal Bunt of Wheat

Journal of Fungi ◽

10.3390/jof7020103 ◽

2021 ◽

Vol 7 (2) ◽

pp. 103

Author(s):

Malkhan Singh Gurjar ◽

Rashmi Aggarwal ◽

Shekhar Jain ◽

Sapna Sharma ◽

Jagmohan Singh ◽

...

Keyword(s):

Multilocus Sequence Typing ◽

Sequence Similarity ◽

Uttar Pradesh ◽

Translation Initiation Factor ◽

Initiation Factor ◽

Karnal Bunt ◽

Polymorphism Analysis ◽

Nucleotide Polymorphisms ◽

Tilletia Indica ◽

Single Nucleotide

Karnal bunt of wheat is an internationally quarantined disease affecting trade, quality, and production of wheat. During 2015–2016, a severe outbreak of Karnal bunt disease occurred in north-western plain zone of India. The present study was undertaken to decipher genetic variations in Indian isolates of Tilletia indica collected from different locations. Seven multilocus sequence fragments were selected to differentiate and characterize these T. indica isolates. A phylogenetic tree constructed based on pooled sequences of actin-related protein 2 (ARP2), β-tubulin (TUB), eukaryotic translation initiation factor 3 subunit A (EIF3A), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), histone 2B (H2B), phosphoglycerate kinase (PGK), and serine/threonine-protein kinase (STPK) showed that isolate KB-11 (Kaithal, Haryana) was highly conserved as it was located in cluster 1 and has the maximum sequence similarity with the reference strain. Other isolates in cluster 1 included KB-16 and KB-17, both from Uttar Pradesh, and KB-19 from Haryana. Isolates KB-07 (Jind, Haryana) and KB-18 (Mujaffar Nagar, Uttar Pradesh) were the most diverse and grouped in a subgroup of cluster 2. Maximum numbers of single nucleotide polymorphisms (SNPs) (675) were in the PGK gene across the T. indica isolates. The minimum numbers of SNPs (67) were in KB-11 (Kaithal, Haryana), while the maximum number of SNPs (165) was identified in KB-18, followed by 164 SNPs in KB-14. KB-18 isolate was found to be the most diverse amongst all T. indica isolates. This first study on multilocus sequence typing (MLST) revealed that the population of T. indica was highly diverse.

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The Same Allele of Translation Initiation Factor 4E Mediates Resistance Against Two Potyvirus spp. in Pisum sativum

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-20-9-1075 ◽

2007 ◽

Vol 20 (9) ◽

pp. 1075-1082 ◽

Cited By ~ 50

Author(s):

M. Bruun-Rasmussen ◽

I. S. Møller ◽

G. Tulinius ◽

J. K. R. Hansen ◽

O. S. Lund ◽

...

Keyword(s):

Pisum Sativum ◽

Mosaic Virus ◽

Resistance Gene ◽

Translation Initiation ◽

Recessive Gene ◽

Translation Initiation Factor ◽

Initiation Factor ◽

Yellow Mosaic Virus ◽

White Lupin ◽

Coding Region

Pathogenicity of two sequenced isolates of Bean yellow mosaic virus (BYMV) was established on genotypes of Pisum sativum L. reported to carry resistance genes to BYMV and other potyviruses. Resistance to the white lupin strain of BYMV (BYMV-W) is inherited as a recessive gene named wlv that maps to linkage group VI together with other Potyvirus resistances. One of these, sbm1, confers resistance to strains of Pea seedborne mosaic virus and previously has been identified as a mutant allele of the eukaryotic translation initiation factor 4E gene (eIF4E). Sequence comparison of eIF4E from BYMV-W-susceptible and –resistant P. sativum genotypes revealed a polymorphism correlating with the resistance profile. Expression of eIF4E from susceptible plants in resistant plants facilitated BYMV-W infection in inoculated leaves. When cDNA of BYMV-W was agroinoculated, resistance mediated by the wlv gene frequently was overcome, and virus from these plants had a codon change causing an Arg to His change at position 116 of the predicted viral genome-linked protein (VPg). Accordingly, plants carrying the wlv resistance gene were infected upon inoculation with BYMV-W derived from cDNA with a His codon at position 116 of the VPg coding region. These results suggested that VPg determined pathogenicity on plants carrying the wlv resistance gene and that wlv corresponded to the sbm1 allele of eIF4E.

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Adenine Base Editor Creates Novel Substitution Mutations in eIF4G Gene of Rice

Madras Agricultural Journal ◽

10.29321/maj.10.000548 ◽

2021 ◽

Vol 108 (special) ◽

Author(s):

Yaiphabi Kumam ◽

◽

Rajadurai G ◽

Kumar K K ◽

Varanavasiappan S ◽

...

Keyword(s):

Translation Initiation Factor ◽

Initiation Factor ◽

Missense Mutations ◽

Amino Acid Residues ◽

Single Nucleotide ◽

Base Editing ◽

Rice Tungro Disease ◽

Substitution Mutations ◽

Resistant Genotypes ◽

Adenine Base

Two single nucleotide polymorphic mutations and deletion affecting Y1059V1060V1061 amino acid residues in a host translation initiation factor four gamma (eIF4G) gene in rice are reported to confer resistance to rice tungrospherical virus in resistant genotypes. A CRISPR-based adenine base editing vector was used to target these residues in a susceptible indica cultivar, ASD16.Agrobacterium-mediated transformation of ASD16 generated 16 missense mutants and two deletion mutants. Substitution mutations occurred at A5> G5 and A4> G4, where 5.5 % and 3.37 % of adenosines got converted to guanosines, respectively. The mutantsgenerated had missense mutations affecting the YVV residues and the residues immediately adjacent to YVV.Thus,these novel mutationsare promising candidates in imparting resistance against rice tungro disease.

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