Reverse Genetics of TheParamyxoviridae

This chapter describes the experiments using the technology of nonsegmented negative-strand virus genome rescue in paramyxoviruses, which led to the recovery of infectious virus from complementary DNA (cDNA) and considers the rescue of infectious virus from the members of each of the four genera for which it has been achieved. Reverse genetics of nonsegmented negative-strand viruses has opened up avenues of study that could not be pursued by conventional mutational analysis. Since the time that measles virus was first rescued, representatives of four of the five genera of Paramyxoviridae have been rescued from cDNA clones into infectious virus. Apart from being used in proof-of-principle experiments, these reverse genetics systems have been used to study the addition or deletion of whole genes as well as the identification of “luxury” functions and putative immune system-modulating proteins. The family Paramyxoviridae is divided into two subfamilies––the Paramyxovirinae and the Pneumovirinae—which contain three and two genera, respectively. Although there are some differences, the general pattern of the genome organization of the members of the Paramyxoviridae is very similar both to each other and to that of other Mononegavirales.