All cells contain RNA. It is located in the cell cytoplasm, nucleus, ribosomes, chromosomes, mitochondria, chloroplasts etc. 90% of the RNA of the cell is in the cytoplasm and 10% of the RNA is in the nucleus. Some bacteria E. coli, Xanthomonas, Cyanobacteria, Francisella etc. contain RNA. Most plant viruses contain RNA. RNA viruses such as TMV, HIV, dengue, polio, mumps, measles, measles, rabies, influenza, arbovirus, coronavirus, reovirus, rice dwarf virus, retrovirus etc.