Parasitic helminths infecting humans are highly prevalent infecting ∼2 billion people worldwide, causing inflammatory responses, malnutrition and anemia that are the primary cause of morbidity. In addition, helminth infections of cattle have a significant economic impact on livestock production, milk yield and fertility. The etiological agents of helminth infections are mainly Nematodes (roundworms) and Platyhelminths (flatworms). G-quadruplexes (G4) are unusual nucleic acid structures formed by G-rich sequences that can be recognized by specific G4 ligands. Here we used the G4Hunter Web Tool to identify and compare potential G4 sequences (PQS) in the nuclear and mitochondrial genomes of various helminths to identify G4 ligand targets. PQS are nonrandomly distributed in these genomes and often located in the proximity of genes. Unexpectedly, a Nematode, Ascaris lumbricoides, was found to be highly enriched in stable PQS. This species can tolerate high-stability G4 structures, which are not counter selected at all, in stark contrast to most other species. We experimentally confirmed G4 formation for sequences found in four different parasitic helminths. Small molecules able to selectively recognize G4 were found to bind to Schistosoma mansoni G4 motifs. Two of these ligands demonstrated potent activity both against larval and adult stages of this parasite.

• MeSH
• cizopasní červi genetika   MeSH
• G-kvadruplexy * MeSH
• genom MeSH
• hlístice * genetika   MeSH
• lidé MeSH
• ligandy MeSH
• paraziti genetika   MeSH
• ploštěnci * genetika   MeSH
• skot MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ligandy MeSH

Nucleic acid-binding proteins are traditionally divided into two categories: With the ability to bind DNA or RNA. In the light of new knowledge, such categorizing should be overcome because a large proportion of proteins can bind both DNA and RNA. Another even more important features of nucleic acid-binding proteins are so-called sequence or structure specificities. Proteins able to bind nucleic acids in a sequence-specific manner usually contain one or more of the well-defined structural motifs (zinc-fingers, leucine zipper, helix-turn-helix, or helix-loop-helix). In contrast, many proteins do not recognize nucleic acid sequence but rather local DNA or RNA structures (G-quadruplexes, i-motifs, triplexes, cruciforms, left-handed DNA/RNA form, and others). Finally, there are also proteins recognizing both sequence and local structural properties of nucleic acids (e.g., famous tumor suppressor p53). In this mini-review, we aim to summarize current knowledge about the amino acid composition of various types of nucleic acid-binding proteins with a special focus on significant enrichment and/or depletion in each category.

• Klíčová slova
• DNA, G-quadruplex, RNA, Z-DNA, Z-RNA, amino acid composition, cruciform, i-motif, protein binding, triplex,
• MeSH
• DNA vazebné proteiny genetika   MeSH
• DNA genetika   ultrastruktura   MeSH
• G-kvadruplexy MeSH
• konformace nukleové kyseliny * MeSH
• leucinové zipy genetika   MeSH
• lidé MeSH
• nukleoproteiny genetika   ultrastruktura   MeSH
• RNA chemie   ultrastruktura   MeSH
• sekvence aminokyselin genetika   MeSH
• transportní proteiny genetika   ultrastruktura   MeSH
• Z-DNA MeSH
• zinkové prsty genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• DNA vazebné proteiny MeSH
• DNA MeSH
• nukleoproteiny MeSH
• RNA MeSH
• transportní proteiny MeSH
• Z-DNA MeSH

The tumor suppressor functions of p53 and its roles in regulating the cell cycle, apoptosis, senescence, and metabolism are accomplished mainly by its interactions with DNA. p53 works as a transcription factor for a significant number of genes. Most p53 target genes contain so-called p53 response elements in their promoters, consisting of 20 bp long canonical consensus sequences. Compared to other transcription factors, which usually bind to one concrete and clearly defined DNA target, the p53 consensus sequence is not strict, but contains two repeats of a 5'RRRCWWGYYY3' sequence; therefore it varies remarkably among target genes. Moreover, p53 binds also to DNA fragments that at least partially and often completely lack this consensus sequence. p53 also binds with high affinity to a variety of non-B DNA structures including Holliday junctions, cruciform structures, quadruplex DNA, triplex DNA, DNA loops, bulged DNA, and hemicatenane DNA. In this review, we summarize information of the interactions of p53 with various DNA targets and discuss the functional consequences of the rich world of p53 DNA binding targets for its complex regulatory functions.

• Klíčová slova
• consensus sequence, cruciform, local DNA structures, p53, protein-DNA interactions,
• MeSH
• DNA chemie   metabolismus   MeSH
• konformace nukleové kyseliny MeSH
• konformace proteinů MeSH
• konsenzuální sekvence MeSH
• lidé MeSH
• molekulární modely MeSH
• nádorový supresorový protein p53 chemie   metabolismus   MeSH
• sekvence aminokyselin MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• DNA MeSH
• nádorový supresorový protein p53 MeSH