title: Tomato 26S Proteasome subunit RPT4a regulates ToLCNDV transcription and activates hypersensitive response in tomato.
abstract: Involvement of 26S proteasomal subunits in plant pathogen-interactions, and the roles of each subunit in independently modulating the activity of many intra- and inter-cellular regulators controlling physiological and defense responses of a plant were well reported. In this regard, we aimed to functionally characterize a Solanum lycopersicum 26S proteasomal subunit RPT4a (SlRPT4) gene, which was differentially expressed after Tomato leaf curl New Delhi virus (ToLCNDV) infection in tolerant cultivar H-88-78-1. Molecular analysis revealed that SlRPT4 protein has an active ATPase activity. SlRPT4 could specifically bind to the stem-loop structure of intergenic region (IR), present in both DNA-A and DNA-B molecule of the bipartite viral genome. Lack of secondary structure in replication-associated gene fragment prevented formation of DNA-protein complex suggesting that binding of SlRPT4 with DNA is secondary structure specific. Interestingly, binding of SlRPT4 to IR inhibited the function of RNA Pol-II and subsequently reduced the bi-directional transcription of ToLCNDV genome. Virus-induced gene silencing of SlRPT4 gene incited conversion of tolerant attributes of cultivar H-88-78-1 into susceptibility. Furthermore, transient overexpression of SlRPT4 resulted in activation of programmed cell death and antioxidant enzymes system. Overall, present study highlights non-proteolytic function of SlRPT4 and their participation in defense pathway against virus infection in tomato.
authors.affiliation: National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi-110067, India.|School of Life Sciences, Jawaharlal Nehru University, New Delhi-110067, India.
authors.forename: Pranav Pankaj
authors.initials: PP
authors.lastname: Sahu
authors.affiliation: National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi-110067, India.
authors.forename: Namisha
authors.initials: N
authors.lastname: Sharma
authors.affiliation: National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi-110067, India.
authors.forename: Swati
authors.initials: S
authors.lastname: Puranik
authors.affiliation: School of Life Sciences, Jawaharlal Nehru University, New Delhi-110067, India.
authors.forename: Supriya
authors.initials: S
authors.lastname: Chakraborty
authors.affiliation: National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi-110067, India.
authors.forename: Manoj
authors.initials: M
authors.lastname: Prasad
mesh_terms: D053839:Begomovirus / Q000235:genetics / Q000254:growth & development; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D016679:Genome, Viral; D054884:Host-Pathogen Interactions / Q000235:genetics* / Q000276:immunology; D055029:Inverted Repeat Sequences; D018551:Solanum lycopersicum / Q000235:genetics* / Q000276:immunology / Q000821:virology; D010935:Plant Diseases / Q000235:genetics* / Q000276:immunology / Q000821:virology; D057865:Plant Immunity / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex / Q000235:genetics* / Q000378:metabolism; D011485:Protein Binding; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D014158:Transcription, Genetic
chemical_list: D004279:DNA, Viral; D010940:Plant Proteins; D021122:Protein Subunits; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease