Identifying quantitative sncRNAs signature using global sequencing as a potential biomarker for tuberculosis diagnosis and their role in regulating host response.

Objectives: The study aimed to identify a quantitative signature of circulating small non-coding RNAs (sncRNAs) as a biomarker for pulmonary tuberculosis disease (active-TB/ATB) and explore their regulatory roles in host-pathogen interactions and disease progression.

Methods: We conducted a cross-sectional study recruiting subjects diagnosed with active-TB (drug-sensitive and drug-resistant) and healthy controls. Sera samples were collected and utilized for preparing small RNA libraries.

Tudor domain proteins in protozoan parasites and characterization of Plasmodium falciparum tudor staphylococcal nuclease.

RNA-binding proteins play key roles in post-transcriptional regulation of gene expression. In eukaryotic cells, a multitude of RNA-binding proteins with several RNA-binding domains/motifs have been described. Here, we show the existence of two Tudor domain containing proteins, a survival of motor neuron (SMN)-like protein and a Staphylococcus aureus nuclease homologue referred to as TSN, in Plasmodium and other protozoan parasites.

Food vacuole targeting and trafficking of falcipain-2, an important cysteine protease of human malaria parasite Plasmodium falciparum.

Malaria proteases are attractive anti-malarial targets because of their roles in parasite development and infection. Falcipain-2 (FP-2), a food vacuole cysteine protease in Plasmodium falciparum, is involved in hemoglobin degradation and cleavage of cytoskeletal elements. To understand the route of trafficking and identify the signals involved in trafficking to food vacuole, we have generated transgenic parasites expressing green fluorescent protein (GFP) fusion proteins comprising of N-terminal regions of falcipain-2 fused to GFP.

Immunogenicity and protective efficacy of Escherichia coli expressed Plasmodium falciparum merozoite surface protein-1(42) using human compatible adjuvants.

The C-terminal 42-kDa fragment of the merozoite surface protein-1 of Plasmodium falciparum (PfMSP-1(42)) was expressed as a recombinant protein in Escherichia coli and purified to near homogeneity. We tested the immunogenicity of recombinant PfMSP-1(42) in three clinically acceptable adjuvants (Montanide ISA 720, alum and MF59) in mice and in rabbits. High antibody responses were obtained with two adjuvant formulations with IgGl being the predominant immunoglobulin isotype.

A role of falcipain-2, principal cysteine proteases of Plasmodium falciparum in merozoite egression.

The process of merozoite release in Plasmodium falciparum involves rupture of the parasitophorous vacuole membrane and erythrocyte plasma membrane. Through the use of protease inhibitors that halt the merozoite release, a number of parasite proteases, especially serine, aspartic, and cysteine proteases, have been implicated in the schizont rupture. To understand the precise role of cysteine proteases in the merozoite release, in the present study, we treated P.

Identification of karyopherin beta as an immunogenic antigen of the malaria parasite using immune mice and human sera.

A differential immunoscreening of the lambdagt11 Plasmodium falciparum genomic expression library was carried out using anti-P. yoelii sera (convalescent-phase mouse sera) and immune sera collected from healthy adults, to identify novel cross-reactive and possibly protective antigens of the parasite. One clone, with an insert size of 1132 bp that reacted strongly with both the sera was selected.

Exploring the role of putative active site amino acids and pro-region motif of recombinant falcipain-2: a principal hemoglobinase of Plasmodium falciparum.

Falcipain-2 is one of the principal hemoglobinases of Plasmodium falciparum, a human malaria parasite. It has a typical papain family cysteine protease structural organization, a large pro-domain, a mature domain with conserved active site amino acids. Pro-domain of falcipain-2 also contains two important conserved motifs, "GNFD" and "ERFNIN.

RNA interference: biology, mechanism, and applications.

Double-stranded RNA-mediated interference (RNAi) is a simple and rapid method of silencing gene expression in a range of organisms. The silencing of a gene is a consequence of degradation of RNA into short RNAs that activate ribonucleases to target homologous mRNA. The resulting phenotypes either are identical to those of genetic null mutants or resemble an allelic series of mutants.

In vivo gene silencing in Plasmodium berghei--a mouse malaria model.

RNA interference (RNAi) has emerged as a specific and efficient tool to silence gene expression in a variety of organisms and cell lines. An important prospect for RNAi technology is its possible application in the treatment of diseases using short interfering RNAs (siRNAs). However, the effect of siRNAs in adult animals and their potential to treat or prevent diseases are yet to be fully investigated.

Double-stranded RNA-mediated gene silencing of cysteine proteases (falcipain-1 and -2) of Plasmodium falciparum.

Malaria remains a public health problem of enormous magnitude, affecting over 500 million people every year. Lack of success in the past in the development of new drug/vaccines has mainly been attributed to poor understanding of the functions of different parasite proteins. Recently, RNA interference (RNAi) has emerged as a simple and incisive technique to study gene functions in a variety of organisms.