Abstract
Hematophagous insects act as the major reservoirs of infectious agents due to their intimate contact with a large variety of vertebrate hosts. Lutzomyia longipalpis is the main vector of Leishmania chagasi in the New World, but its role as a host of viruses is poorly understood. In this work, Lu. longipalpis RNA libraries were subjected to progressive assembly using viral profile HMMs as seeds. A sequence phylogenetically related to fungal viruses of the genus Mitovirus was identified and this novel virus was named Lul-MV-1. The 2697-base genome presents a single gene coding for an RNA-directed RNA polymerase with an organellar genetic code. To determine the possible host of Lul-MV-1, we analyzed the molecular characteristics of the viral genome. Dinucleotide composition and codon usage showed profiles similar to mitochondrial DNA of invertebrate hosts. Also, the virus-derived small RNA profile was consistent with the activation of the siRNA pathway, with size distribution and 5′ base enrichment analogous to those observed in viruses of sand flies, reinforcing Lu. longipalpis as a putative host. Finally, RT-PCR of different insect pools and sequences of public Lu. longipalpis RNA libraries confirmed the high prevalence of Lul-MV-1. This is the first report of a mitovirus infecting an insect host.
Highlights
Viruses are the most abundant biological entities in the biosphere, being found in every environment and infecting a wide range of organisms, such as plants, insects, mammals, and microorganisms [1,2,3]
We investigate the diversity of viruses circulating in the sandfly Lutzomyia longipalpis, the most important vector of Leishmania chagasi in the New World
In a first attempt to detect possible viral sequences in Lu. longipalpis, we tested a set of 506 profile HMMs selected from the vFam database against two sequencing datasets of long RNA (lRNA) data, totaling 48 million reads
Summary
Viruses are the most abundant biological entities in the biosphere, being found in every environment and infecting a wide range of organisms, such as plants, insects, mammals, and microorganisms [1,2,3]. We investigate the diversity of viruses circulating in the sandfly Lutzomyia longipalpis, the most important vector of Leishmania chagasi in the New World For this goal, we use three innovative methods: (1) profile HMMs to interrogate public long RNA sequencing data, (2) progressive assembly using profile HMMs as seeds, and (3) small RNA profiles to differentiate exogenous from endogenous viral sequences. We use three innovative methods: (1) profile HMMs to interrogate public long RNA sequencing data, (2) progressive assembly using profile HMMs as seeds, and (3) small RNA profiles to differentiate exogenous from endogenous viral sequences Using this integrated approach, we identify and describe Lul-MV-1 (Lutzomyia longipalpis mitovirus 1), the first mitovirus found to infect the mitochondria of an insect host
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
