Genetic variability and evolutionary dynamics of atypical Papaya ringspot virus infecting Papaya

Abstract

Papaya ringspot virus biotype-P is a detrimental pathogen of economically important papaya and cucurbits worldwide. The mutation prone feature of this virus perhaps accounts for its geographical dissemination. In this study, investigations of the atypical PRSV-P strain was conducted based on phylogenetic, recombination and genetic differentiation analyses considering of it’s likely spread across India and Bangladesh. Full length genomic sequences of 38 PRSV isolates and 35 CP gene sequences were subjected to recombination analysis. A total of 61 recombination events were detected in aligned complete PRSV genome sequences. 3 events were detected in complete genome of PRSV strain PK whereas one was in its CP gene sequence. The PRSV-PK appeared to be recombinant of a major parent from Bangladesh. However, the genetic differentiation based on full length genomic sequences revealed less frequent gene flow between virus PRSV-PK and the population from America, India, Colombia, other Asian Countries and Australia. Whereas, frequent gene flow exists between Pakistan and Bangladesh virus populations. These results provided evidence correlating geographical position and genetic distances. We speculate that the genetic variations and evolutionary dynamics of this virus may challenge the resistance developed in papaya against PRSV and give rise to virus lineage because of its atypical emergence where geographic spread is already occurring.

Survey, Detection, Characterization of Papaya Ringspot Virus from Southern India and Management of Papaya Ringspot Disease

“…Recombination is an important factor in promoting virus evolution, which can increase genomic biodiversity [ 86 ] and enhance the virulence of the virus to expand its host range [ 87 ]. The diversity of PRSV varies from region to region due to the occurrence of spatial recombination and temporal evolution within the province [ 88 ]. PRSV diversity appears to be changing at different rates, presumably driven by introductions, movement of plant materials, geographical isolation, and disease management practices [ 89 ].…”

In-silico comparative modeling and interaction studies of PRSV proteins - Accelerated towards dissection of structure based evolutionary divergence and functional interaction of virus within the host

“…In the current study three functionally vital proteins of PRSV-PK strain has been modeled using compatible modeling servers. The nucleotide based genetic diversity studies on CP gene of PRSV-PK strain has already been conducted extensively [6,9]. However, the diversity exploration of virus genome is not only confined to molecular approaches including recombination and phylogenetics, rather structural information of virus proteins has shown significant contribution towards virus diversity in terms of its structure-function relationship [32].…”

“…The nucleotide based molecular and evolutionary studies provide sufficient insight into the genetic variability of the virus strain [8][9][10][11][12]. However, the differential role of essential virus proteins in terms of virus divergence and evolution could also be clarified through their structural prediction [13].…”

Occurrence, Distribution, and Management of Aphid-Transmitted Viruses in Cucurbits in Spain

“…Serologically, PRSV has been divided into two biotypes; the papaya-infecting biotype P (PRSV-P) and the cucurbit-infecting biotype W (PRSV-W). PRSV-P was first described from papaya in Hawaii, and PRSV-W was formerly known as watermelon mosaic virus 1 (WMV-1), which might have appeared in Australia 20 years before PRSV-P, suggesting that PRSV-P may have originated from PRSV-W [ 60 ]. PRSV has a very restricted host range, mainly infecting members of the Cucurbitaceae family, with the exception of the papaya from which it takes its name, and some non-cucurbit species such as Chenopodium [ 11 ].…”