We are glad to announce that Ramakrishna Mission Vivekananda Educational and Research Institute (RKMVERI) will be conducting a special colloquium on “Plant-Microbe interaction and MicroRNAs” on 09 September 2022, 12 noon at Seminar Hall, Narendrapur Campus.

Speaker : Dr Bhubaneswar Pradhan
Co-ordinator: Abhijit Chakrabarti

Plants, during their life, are exposed to a multitude of pathogens and pests that cause major crop losses in agriculture. To protect themselves, they have evolved several intricate mechanisms and possess an innate immune system that efficiently detects potential microbial pathogens. The regulation of immune response genes has been studied both at the transcriptional and posttranscriptional levels. At the post-transcriptional level, the microRNAs (miRNAs) mediated gene regulation is achieved in a sequence-specific manner by targeting genome-encoded transcripts through transcript cleavage or translational inhibition. The miRNAs are short non-coding RNAs of 19-24 nt length originate from MIRNA genes that are transcribed by RNA polymerase II. Using two important plant pathogens as our model; a virus infecting tomatoes and a fungus attacking rice, we aim to understand the underlying mechanism of miRNA-mediated host-pathogen interaction. Tomato leaf curl New Delhi virus (ToLCNDV), being one of the major threats to tomato plants, we attempted to profile the up-and-down-regulation of different miRNAs in the context of ToLCNDV infection. Small RNA deep sequencing from healthy and ToLCNDV-infected leaves of tomatoes was carried out by adopting the next-generation sequencing (NGS) approach. The bioinformatics prediction and wet lab validation were also performed which revealed that the virus modulated the global miRNA expression of the host. Rice blast disease caused by the filamentous fungus Magnaporthe oryzae leads to a loss of approximately 10–30% of the annual rice yield globally. Many rice miRNAs and their corresponding target genes/transcripts have been identified and characterized in response to M. oryzae infection. The transcripts regulated by these miRNAs could be potentially targeted to achieve plant resistance to pathogen infection. However, the M. oryzae encoded transcripts could also be regulated by the rice miRNAs during rice-M. oryzae interaction and hence can be hypothesized as an alternative strategy for rice immunity towards M. oryzae. The gene expression and regulation mechanism of both host and pathogen by host miRNAs could be of immense importance to achieve durable resistance to M. oryzae infection. We analyzed many M. oryzae transcripts targeted by rice miRNAs using an in silico approach. Out of seven hundred thirty-eight available rice miRNAs, 12 miRNA families were found to be the putative regulator of many pathogenicity-related transcripts of the pathogen synthesized during M. oryzae rice interaction. In the future, functional validation of the identified miRNAs of rice and their corresponding target transcripts of M. oryzae should be made to devise novel miRNA-mediated disease control strategies for rice blast disease.