Aedes aegypti microRNA, miR-2944b-5p interacts with 3'UTR of chikungunya virus and cellular target vps-13 to regulate viral replication

Abstract

Background RNA interference is among the most important mechanisms that serve to restrict virus replication within mosquitoes, where microRNAs (miRNAs) are important in regulating viral replication and cellular functions. These miRNAs function by binding to complementary sequences mostly in the untranslated regions of the target. Chikungunya virus (CHIKV) genome consists of two open reading frames flanked by 5′ and 3′ untranslated regions on the two sides. A recent study from our laboratory has shown that Aedes miRNAs are regulated during CHIKV infection. The present study was undertaken to further understand the role of these miRNAs in CHIKV replication. Methods/Findings We observe that miR-2944b-5p binds to the 3′ untranslated region of CHIKV and the binding is abated when the binding sites are abolished. Loss-of-function studies of miR-2944b-5p using antagomirs, both in vitro and in vivo , reveal an increase in CHIKV viral replication, thereby directly implying a role of miR-2944b-5p in CHIKV replication. We further showed that the mitochondrial membrane potential of the mosquito cells is maintained by this miRNA during CHIKV replication, and cellular factor vps-13 plays a contributing role. Conclusions Our study has opened new avenues to understand vector-virus interactions and provides novel insights into CHIKV replication in Aedes aegypti . Furthermore, our study has shown miR-2944b-5p to be playing role, where one of its target vps-13 also contributes, in maintaining mitochondrial membrane potential in Aedes aegypti .

Role of MicroRNAs in Bone Pathology during Chikungunya Virus Infection

“…Besides having an imperative role in physiological functions, the aberrant expression of miRNAs is associated with pathogenesis of various diseases including viral infections [ 21 , 22 , 23 ]. Recently, altered expression of several miRNAs (listed in Table 1 ) has been observed during CHIKV infection [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ].…”

“…To establish infection and increase virus survival in a mosquito vector, viruses modify the transcriptional profile of the vector [ 63 ]. In Aag-2 cells, aae-miR-2944b-5p and aae-miR-2b were observed to have binding sites for the 3′ UTR of CHIKV [ 29 ]. When mosquitoes were treated with antagomiR-2944b-5p, they showed more susceptibility to CHIKV infection compared to untreated control which suggested the role of antagomiR-2944b-5p in viral replication.…”

“…In Ae. aegypti , VPS-13 functions in maintaining the mitochondrial membrane potential (MtMP) [ 29 ]. Interestingly, studies report that host mitochondria are involved in combating the oxidative stress induced during viral infections [ 64 ].…”

“…Interestingly, studies report that host mitochondria are involved in combating the oxidative stress induced during viral infections [ 64 ]. Silencing aae-miR-2944b-5p in Aag-2 cells and infecting with CHIKV increased cellular MtMP, which indicated that aae-miR-2944b-5p interacts with VPS-13 to maintain MtMP [ 29 ]. In humans, VPS-13 is involved in post Golgi apparatus sorting and trafficking.…”

Diverse Defenses: A Perspective Comparing Dipteran Piwi-piRNA Pathways

“…In this review we raise some key questions ( Box 1 ), we primarily discuss the Piwi protein and Piwi-interacting RNA (piRNA) pathways in these two Dipteran lineages and we touch upon the endogenous small interfering RNA (endo-siRNA), a canonical branch of RNAi. Although the microRNA (miRNA) branch of the RNAi pathway critically regulates gene expression during development for all animals [ 19 , 20 ], the role of microRNAs in transposon or virus suppression in insects has been more limited to a few studies [ 21 , 22 , 23 ], or has courted controversy [ 24 , 25 , 26 ]. We refer to [ 27 ] for further reading on this topic.…”