Cells of the reproductive system (germline) have a very important function of transmitting genetic information from parents to offspring. However, recent research has clearly established that in addition to DNA, germ cells also transmit information using epigenome. Epigenetic information includes DNA modification, modification of scaffold proteins involved in DNA packaging and small RNA (sRNA) molecules. My research is focused on studying sRNAs using the roundworm, Caenorhabditis elegans as a model. Apart from transmitting the life experience from parent to offspring, sRNAs also stop the expression of deleterious genes and provide defence against foreign elements in the germline to maintain genome integrity. However, in C. elegans germline, thousands of sRNAs are produced against self-germline genes. These sRNAs are loaded by a specialized Argonaute called CSR-1 which is an essential protein.
In a recent study, we addressed the function of this mysterious sRNA pathway in regulating germline gene expression and we further elucidated the mechanism of biogenesis of CSR-1-associated sRNAs and the crosstalk of the sRNA biogenesis machinery with translation. I am further investigating the transfer of sRNAs produced in response to external stress from soma to germline and their inheritance in the embryo.
Owing to my interest in sRNA biology, during Covid-19 pandemic we started another project, where we identified a miRNA derived from SARS-CoV2 genome, which hijacks host RNAi machinery to silence genes involved in innate immune response in the host.
With extensive background in small RNA biology, epigenetics, and my past PhD experience in infection biology, in future I will study the epigenetic mechanisms underlying host response to pathogen exposure and the mechanism of epigenetic inheritance. Moreover, I will focus on epigenetic variations underlying inter-individual variability observed in host responses to pathogen.