Tomato cultivar tolerant to Tomato leaf curl New Delhi virus infection induces virus-specific short interfering RNA accumulation and defence-associated host gene expression.
Tomato leaf curl New Delhi virus (ToLCNDV) infection causes significant yield loss in tomato. The availability of a conventional tolerance source against this virus is limited in tomato. To understand the molecular mechanism of virus tolerance in tomato, the abundance of viral genomic replicative intermediate molecules and virus-directed short interfering RNAs (siRNAs) by the host plant in a naturally tolerant cultivar H-88-78-1 and a susceptible cultivar Punjab Chhuhara at different time points after agroinfection was studied. We report that less abundance of viral replicative intermediate in the tolerant cultivar may have a correlation with a relatively higher accumulation of virus-specific siRNAs. To study defence-related host gene expression in response to ToLCNDV infection, the suppression subtractive hybridization technique was used. A library was prepared from tolerant cultivar H-88-78-1 between ToLCNDV-inoculated and Agrobacterium mock-inoculated plants of this cultivar at 21 days post-inoculation (dpi). A total of 106 nonredundant transcripts was identified and classified into 12 different categories according to their putative functions. By reverse Northern analysis and quantitative real-time polymerase chain reaction (qRT-PCR), we identified the differential expression pattern of 106 transcripts, 34 of which were up-regulated (>2.5-fold induction). Of these, eight transcripts showed more than four fold induction. qRT-PCR analysis was carried out to obtain comparative expression profiling of these eight transcripts between Punjab Chhuhara and H-88-78-1 on ToLCNDV infection. The expression patterns of these transcripts showed a significant increase in differential expression in the tolerant cultivar, mostly at 14 and 21 dpi, in comparison with that in the susceptible cultivar, as analysed by qRT-PCR. The probable direct and indirect relationship of siRNA accumulation and up-regulated transcripts with the ToLCNDV tolerance mechanism is discussed.
Sahu
Pranav Pankaj
PP
National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi-110067, India.
Rai
Neeraj K
NK
Chakraborty
Supriya
S
Singh
Major
M
Chandrappa
Prasanna H
PH
Ramesh
Bandarupalli
B
Chattopadhyay
Debasis
D
Prasad
Manoj
M
D053839:Begomovirus / Q000276:immunology / Q000472:pathogenicity*; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000276:immunology*; D018551:Solanum lycopersicum / Q000235:genetics* / Q000276:immunology / Q000382:microbiology*; D010935:Plant Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology*; D018749:RNA, Plant / Q000235:genetics / Q000502:physiology*; D034741:RNA, Small Interfering / Q000235:genetics / Q000502:physiology*
D018749:RNA, Plant; D034741:RNA, Small Interfering