Search results for " Codon"

Sequence variation in couch potato and its effects on life-history traits in a northern malt fly, Drosophila montana

2011

Abstract Couch potato ( cpo ) has previously been connected to reproductive diapause in several insect species including Drosophila melanogaster , where it has been suggested to provide a link between the insulin signalling pathway and the hormonal control of diapause. In the first part of the study we sequenced nearly 3.6 kb of this gene in a northern Drosophila species ( Drosophila montana ) with a robust photoperiodically determined diapause and found several types of polymorphisms along the sequenced area. We also found variation among five Drosophila virilis group species in the length of the 5th exon of cpo and in the site of the stop codon at the end of this exon. The second part of …

Allium kyrenium (Amaryllidaceae), a new species from Northern Cyprus.

2015

Allium kyrenium, a new species of Allium sect. Codonoprasum, is described and illustrated from northern Cyprus. It is a very circumscribed geophyte growing on the calcareous cliffs of the Kyrenia range. This diploid species, with a somatic chromosome number 2n = 16, shows close morphological relationships with A. stamineum, a species complex distributed in the eastern Mediterranean area. Its morphology, karyology, leaf anatomy, ecology, conservation status and taxonomical relationships with the allied species belonging to the A. stamineum group are examined.

Phylogeny of the autumn-flowering species of A. sect. Codonoprasum from the Mediterranean region.

2009

A method to isolate cDNA-quality RNA from adult conifer needles and a psbA cDNA from Norway spruce

1996

Summary In order to investigate the expression of the psbA gene in damaged and undamaged Norway spruce trees ( Picea abies ) a cDNA clone encoding the D1 protein was isolated via RT-PCR. Applying a method developed by Schneiderbauer et al. (1991) with some modifications, we were able to obtain the required RNA from mature needles and successfully reverse transcribe it into cDNA. Sequence analysis of the cDNA clone revealed an open reading frame (ORF) encoding a 353 amino acid polypeptide that is highly homologous to the D1 protein sequences deduced from higher plant psbA genes. A 4 bp insertion, directly following the stop codon ochre (TAA), was found by comparison with two Pinus species, t…

Allium sphaeronixum (Amaryllidaceae), A New Species from Turkey

2023

In this paper, Allium sphaeronixum, a new species of the sect. Codonoprasum from Turkey, is described and illustrated. The new species is endemic to Central Anatolia, limited to the area of Nevşehir, where it grows on sandy or rocky soil at an elevation of 1000–1300 m a.s.l. Its morphology, phenology, karyology, leaf anatomy, seed testa micromorphology, chorology, and conservation status are examined in detail. The taxonomic relationships with the closest allied species, A. staticiforme and A. myrianthum, are also highlighted and discussed.

Molecular Approaches Fighting Nonsense

2021

Nonsense mutations are the result of single nucleotide substitutions in the DNA that change a sense codon (coding for an amino acid) to a nonsense or premature termination codon (PTC) within the coding region of the mRNA [...]

Investigating the inhibition of FTSJ1 a tryptophan tRNA-specific 2’-O-methyltransferase by NV TRIDs, as a mechanism of readthrough in nonsense mutate…

2023

Abstract: Cystic Fibrosis (CF) is an autosomal recessive genetic disease caused by mutations in the CFTR gene, coding for the CFTR chloride channel. About 10% of the CFTR gene mutations are "stop" mutations, which generate a Premature Termination Codon (PTC), thus synthesizing a truncated CFTR protein. A way to bypass PTC relies on ribosome readthrough, which is the ri-bosome’s capacity to skip a PTC, thus generating a full-length protein. “TRIDs” are molecules exerting ribosome readthrough; for some, the mechanism of action is still under debate. We in-vestigate a possible mechanism of action (MOA) by which our recently synthesized TRIDs, namely NV848, NV914, and NV930, could exert their r…

FEDRO: a software tool for the automatic discovery of candidate ORFs in plants with c →u RNA editing

2019

RNA editing is an important mechanism for gene expression in plants organelles. It alters the direct transfer of genetic information from DNA to proteins, due to the introduction of differences between RNAs and the corresponding coding DNA sequences. Software tools successful for the search of genes in other organisms not always are able to correctly perform this task in plants organellar genomes. Moreover, the available software tools predicting RNA editing events utilise algorithms that do not account for events which may generate a novel start codon. We present Fedro, a Java software tool implementing a novel strategy to generate candidate Open Reading Frames (ORFs) resulting from Cytidi…

Extremely High Mutation Rate of HIV-1 In Vivo.

2015

Rates of spontaneous mutation critically determine the genetic diversity and evolution of RNA viruses. Although these rates have been characterized in vitro and in cell culture models, they have seldom been determined in vivo for human viruses. Here, we use the intrapatient frequency of premature stop codons to quantify the HIV-1 genome-wide rate of spontaneous mutation in DNA sequences from peripheral blood mononuclear cells. This reveals an extremely high mutation rate of (4.1 ± 1.7) × 10−3 per base per cell, the highest reported for any biological entity. Sequencing of plasma-derived sequences yielded a mutation frequency 44 times lower, indicating that a large fraction of viral genomes …

Molecular, Genetic and Epidemiologic Studies on Selective Complete C1q Deficiency in Turkey

2000

Selective complete C1q deficiencies (SCDC1q) of the complement component C1q are rare genetic disorders with high prevalence of lupus-erythematosus-like symptoms and recurrent infections. Among the 41 published cases from 23 families, 10 derive from 6 Turkish families. One particular mutation leading to a stop codon in the C1q A gene was first identified in members of a Gypsy family from the Slovac Republic. Later the same mutation has been found in all cases in four SCDC1q families from Turkey suggesting that one particular defective allele may be present in the populations of Southeastern Europe and Turkey. This study was undertaken to investigate the frequency of C-->T mutation in exon I…