Andrej Lupták

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Ribozymes are thought to have played a pivotal role in the early evolution of life, but relatively few have been identified in modern organisms. We performed an in vitro selection aimed at isolating self-cleaving RNAs from the human genome. The selection yielded several ribozymes, one of which is a conserved mammalian sequence that resides in an intron of(More)
Hepatitis delta virus (HDV) and cytoplasmic polyadenylation element-binding protein 3 (CPEB3) ribozymes form a family of self-cleaving RNAs characterized by a conserved nested double-pseudoknot and minimal sequence conservation. Secondary structure-based searches were used to identify sequences capable of forming this fold, and their self-cleavage activity(More)
Many non-long terminal repeat (non-LTR) retrotransposons lack internal promoters and are co-transcribed with their host genes. These transcripts need to be liberated before inserting into new loci. Using structure-based bioinformatics, we show that several classes of retrotransposons in phyla-spanning arthropods, nematodes, and chordates utilize(More)
The hammerhead ribozyme is a small catalytic RNA motif capable of endonucleolytic (self-) cleavage. It is composed of a catalytic core of conserved nucleotides flanked by three helices, two of which form essential tertiary interactions for fast self-scission under physiological conditions. Originally discovered in subviral plant pathogens, its presence in(More)
One of the major challenges in the development of targeted nanoparticles (NPs) for cancer therapy is to discover targeting ligands that allow for differential binding and uptake by the target cancer cells. Using prostate cancer (PCa) as a model disease, we developed a cell-uptake selection strategy to isolate PCa-specific internalizing 2'-O-methyl RNA(More)
Hepatitis delta virus ribozymes have been proposed to perform self-cleavage via a general acid/base mechanism involving an active-site cytosine, based on evidence from both a crystal structure of the cleavage product and kinetic measurements. To determine whether this cytosine (C75) in the genomic ribozyme has an altered pK(a) consistent with its role as a(More)
Deep sequencing of viral or bacterial nucleic acids monitors the presence and diversity of microbes in select populations and locations. Metagenomic study of mammalian viromes can help trace paths of viral transmissions within or between species. High throughput sequencing of patient and untreated sewage microbiomes showed many sequences with no similarity(More)
Structured functional RNAs are conserved on the level of secondary and tertiary structure, rather than at sequence level, and so traditional sequence-based searches often fail to identify them. Structure-based searches are increasingly used to discover known RNA motifs in sequence databases. We describe the application of the program RNABOB, which performs(More)
Multiple lines of evidence support the hypothesis that the early evolution of life was dominated by RNA, which can both transfer information from generation to generation through replication directed by base-pairing, and carry out biochemical activities by folding into functional structures. To understand how life emerged from prebiotic chemistry we must(More)
Evolve and resequence (E&R) experiments use experimental evolution to adapt populations to a novel environment, then next-generation sequencing to analyse genetic changes. They enable molecular evolution to be monitored in real time on a genome-wide scale. Here, we review the field of E&R experiments across diverse systems, ranging from simple non-living(More)