RNAi-Induced Gene Silencing against Chikungunya and COVID-19: What Have We Learned So Far, and What Is the Way Forward?

RNA interference (RNAi) is a process in which small RNA molecules (such as small interfering RNAs or siRNAs) bind to specific messenger RNAs (mRNAs), leading to its degradation and inhibition of protein synthesis. Our studies have shown that RNAi can effectively silence genes involved in the replication of the Chikungunya virus (CHIKV) in cells. However, these investigations were performed only in laboratory settings and have yet to be tested in human clinical trials.

Comparative assessment of amino acids composition in two types of marine fish silage.

Fish silage is a brown liquefied product achieved by the action of enzymes when finely grounded whole/parts of either single or mixed fish types are subjected to acidification. This study made a comparative assessment of biochemical and nutritive properties, especially the amino acid composition in supernatant phase of formic acid silages prepared from two fish types, Indian mackerel (Rastrelliger kanagurta) and false travely (Lactarius lactarius) representing fat fish (FF, fat content > 5%) and lean fish (LF, fat content < 5%), respectively during 35 days of fermentation (DoF). Significantly higher content of total amino acid (TAA) and free amino acids (FAA) were recorded in FFS (TAA, 41.

Altered microRNA expression signature in Chikungunya-infected mammalian fibroblast cells.

Chikungunya virus (CHIKV) infection can cause severe arthralgia and chronic arthritis in humans. MicroRNAs (miRNA) have demonstrated their potential use as biomarker in variety of human pathologies and infections. This study was conducted to understand the miRNA signature in early CHIKV infection stages.

Hepatitis E virus RNA-dependent RNA polymerase: RNA template specificities, recruitment and synthesis.

Hepatitis E virus (HEV) is a positive-sense RNA virus and member of the genus Orthohepevirus in the family Hepeviridae. Although HEV RNA-dependent RNA polymerase (HEV-RdRp) plays an important role in the HEV life cycle, its template specificities are not completely understood. We expressed HEV-RdRp protein with His-tag in a bacterial system and analysed template specificities using different putative cis-regulatory elements in the HEV genome.

First molecular phylogeny of scorpions of the family Buthidae from India.

Scorpions of the family Buthidae are widespread species in India. While studies are available on diversity and distribution of Indian buthid scorpions, no information is available on the phylogenetic relationships among the members of the family, within India and Asia in general. In the current study, we provide the first molecular phylogeny of buthid scorpions from central western India based on the mitochondrial cytochrome oxidase subunit I (COI) gene.

Hepatitis E virus (HEV)-1 harbouring HEV-4 non-structural protein (ORF1) replicates in transfected porcine kidney cells.

Hepatitis E virus (HEV) is a causative agent of acute hepatitis and a major public health problem in India. There are four mammalian HEV genotypes worldwide. In India, genotype 1 (HEV-1) is restricted to humans whereas genotype 4 (HEV-4) circulates in pigs.

Chikungunya virus susceptibility & variation in populations of Aedes aegypti (Diptera: Culicidae) mosquito from India.

Background & Objectives: Although having immense clinical relevance, yet only a few studies have been targeted to understand the chikungunya virus (CHIKV) susceptibility and growth in Aedes aegypti populations from India. This study was undertaken to investigate CHIKV susceptibility and growth kinetics in Ae. aegypti along with genetic heterogeneity of Ae.

Vector competence of two Indian populations of Culex quinquefasciatus (Diptera: Culicidae) mosquitoes to three West Nile virus strains.

Background & Objectives: Culex quinquefasciatus is one of the principal vectors of West Nile virus (WNV). The mosquito also acts as a bridge vector as it feeds on both birds and humans. In the background of the recent reports of WNV activity in Kerala and Assam with fatalities, a study was initiated to determine the growth kinetics and transmission mechanisms of three strains of WNV in two populations of Cx.

Identification and characterization of cellular proteins interacting with Hepatitis E virus untranslated regions.

Lack of robust cell culture systems for Hepatitis E virus (HEV) infection has hampered understanding of HEV biology. We attempted to identify the host cellular factors that interact with HEV 5' and 3' untranslated regions (UTRs) by RNA affinity chromatography followed by mass spectrometry analysis. Hepatitis E virus genotype-1 (HEV-1) and Hepatitis E virus genotype-4 (HEV-4) and three cell lines (HepG2/C3A, A549 and Caco2) were employed to understand the UTR-host protein interaction.

Asian strain of Batrachochytrium dendrobatidis is widespread in the Western Ghats, India.

We investigated the distribution of Batrachochytrium dendrobatidis (Bd) fungal infections in amphibians of the Western Ghats mountain range in India, based on data from 497 samples. Eight individuals were positive, with genomic equivalents ranging from 2 to 785 zoospores. A single widespread Bd strain identical to the haplotype endemic to Asia was isolated.

Pethia longicauda, a new species of barb (Teleostei: Cyprinidae) from the northern Western Ghats, India.

Pethia longicauda, a new cyprinid fish, is described from Hiranyakeshi River, Krishna drainage, Maharashtra, India. It can be distinguished from congeners based on a combination of characters including: a long caudal peduncle, incomplete lateral line, absence of barbels, upper lip thick and fleshy, distinct lateral fold on snout, 22-24 scales in lateral series, 5-6 lateral-line pored scales, nine predorsal scales, 9-10 prepelvic scales, 15-17 preanal scales, ½3/1/3½ transverse scales, 11-15 pairs of serrae on the distal half of the last unbranched dorsal-fin ray, 11-13 branched pectoral fin rays, 4+26 total vertebrae, 4+5 predorsal vertebrae, 4+13 abdominal and 13 caudal vertebrae, body iridescent silver in color with a black humeral spot, two black blotches on caudal peduncle and dorsal fin usually without any color bands or blotches but in breeding males with two rows of minute, indistinct black spots. 

Serratia odorifera mediated enhancement in susceptibility of Aedes aegypti for chikungunya virus.

Background & Objectives: The susceptibility of the mosquito to the invading pathogen is predominantly dictated by the complex interactions between the mosquito midgut and the surface proteins of the invading pathogen. It is well documented that the midgut microbiota plays an important role in determining the susceptibility of the mosquito to the pathogen. In the present study, we investigated the influence of Serratia odorifera, an endogenous cultivable midgut inhabitant of Aedes aegypti on the chikungunya virus (CHIKV) susceptibility to this mosquito.

Identification of chikungunya virus interacting proteins in mammalian cells.

Identification and characterization of virus host interactions is an essential step for the development of novel antiviral strategies. Very few studies have been targeted towards identification of chikungunya virus (CHIKV) interacting host proteins. In current study, virus overlay protein binding assay (VOPBA) and matrix-assisted laser desorption/ ionization time of flight analysis (MALDI TOF/TOF) were employed for the identification of CHIKV binding proteins in mammalian cells.

White Spot Syndrome Virus infection in Penaeus monodon is facilitated by housekeeping molecules.

White Spot Syndrome Virus (WSSV) is a major pathogen in shrimp aquaculture, and its rampant spread has resulted in great economic loss. Identification of host cellular proteins interacting with WSSV will help in unravelling the repertoire of host proteins involved in WSSV infection. In this study, we have employed one-dimensional and two-dimension virus overlay protein binding assay (VOPBA) followed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to identify the host proteins of Penaeus monodon that could interact with WSSV.

Endemic Asian chytrid strain infection in threatened and endemic anurans of the Northern Western Ghats, India.

The Western Ghats of India harbors a rich diversity of amphibians with more than 77% species endemic to this region. At least 42% of the endemic species are threatened due to several anthropogenic stressors. However, information on amphibian diseases and their impacts on amphibian populations in this region are scarce.

Administration of E2 and NS1 siRNAs inhibit chikungunya virus replication in vitro and protects mice infected with the virus.

Background: Chikungunya virus (CHIKV) has reemerged as a life threatening pathogen and caused large epidemics in several countries. So far, no licensed vaccine or effective antivirals are available and the treatment remains symptomatic. In this context, development of effective and safe prophylactics and therapeutics assumes priority.

Serratia odorifera a midgut inhabitant of Aedes aegypti mosquito enhances its susceptibility to dengue-2 virus.

Mosquito midgut plays a crucial role in its vector susceptibility and pathogen interaction. Identification of the sustainable microflora of the midgut environment can therefore help in evaluating its contribution in mosquito-pathogen interaction and in turn vector competence. To understand the bacterial diversity in the midgut of Aedes aegypti mosquitoes, we conducted a screening study of the gut microbes of these mosquitoes which were either collected from fields or reared in the laboratory "culture-dependent" approach.

Morphometric and allozyme variation in Culex tritaeniorhynchus mosquito populations from India.

Four populations of Culex tritaeniorhynchus (Giles) (Diptera: Culicidae), collected from Bellary, Cuddalore, Pune, and the Microbial Containment Complex laboratory culture in India were analyzed for morphological and allozyme variation. Multivariate analysis based on eight morphological characteristics and three morphometric indices was used to investigate the morphological variations among the four populations. Principal component analysis of the data suggested that siphon, saddle, and anal gills related variables were most important.

Dengue-2-virus-interacting polypeptides involved in mosquito cell infection.

For the design of effective antiviral strategies, understanding the fundamental steps of the virus life cycle, including virus-host interactions, is essential. We performed a virus overlay protein binding assay followed by proteomics for identification of proteins from membrane fractions of A7 (Aedes aegypti) cells, C6/36 (Aedes albopictus) cells and the midgut brush border membrane fraction of Ae. aegypti mosquito that bind to dengue-2 virus.

Biodegradation of allethrin, a pyrethroid insecticide, by an acidomonas sp.

Allethrin is a major mosquito repellent agent. To degrade allethrin present in used mats and the environment, a bacterium capable of utilizing allethrin was isolated. This isolate, an Acidomonas sp.