Dataset Information

Tautomers of a Fluorescent G Surrogate and Their Distinct Photophysics Provide Additional Information Channels.

ABSTRACT: Thienoguanosine ((th) G) is an isomorphic nucleoside analogue acting as a faithful fluorescent substitute of G, with respectable quantum yield in oligonucleotides. Photophysical analysis of (th) G reveals the existence of two ground-state tautomers with significantly shifted absorption and emission wavelengths, and high quantum yield in buffer. Using (TD)-DFT calculations, the tautomers were identified as the H1 and H3 keto-amino tautomers. When incorporated into the loop of (-)PBS, the (-)DNA copy of the HIV-1 primer binding site, both tautomers are observed and show differential sensitivity to protein binding. The red-shifted H1 tautomer is strongly favored in matched (-)/(+)PBS duplexes, while the relative emission of the H3 tautomer can be used to detect single nucleotide polymorphisms. These tautomers and their distinct environmental sensitivity provide unprecedented information channels for analyzing G residues in oligonucleotides and their complexes.

SUBMITTER: Sholokh M

PROVIDER: S-EPMC4978544 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Tautomers of a Fluorescent G Surrogate and Their Distinct Photophysics Provide Additional Information Channels.

Sholokh Marianna M Improta Roberto R Mori Mattia M Sharma Rajhans R Kenfack Cyril C Shin Dongwon D Voltz Karine K Stote Roland H RH Zaporozhets Olga A OA Botta Maurizio M Tor Yitzhak Y Mély Yves Y

Angewandte Chemie (International ed. in English) 20160608 28

Thienoguanosine ((th) G) is an isomorphic nucleoside analogue acting as a faithful fluorescent substitute of G, with respectable quantum yield in oligonucleotides. Photophysical analysis of (th) G reveals the existence of two ground-state tautomers with significantly shifted absorption and emission wavelengths, and high quantum yield in buffer. Using (TD)-DFT calculations, the tautomers were identified as the H1 and H3 keto-amino tautomers. When incorporated into the loop of (-)PBS, the (-)DNA c ...[more]

PMID: 27273741

Similar Datasets

Project description:Despite a recent explosion of research on pattern recognition, in both neuroscience and computer vision, we lack a basic understanding of how most animals perceive and respond to patterns in the wild. Avian brood parasites and their hosts provide an ideal study system for investigating the mechanisms of pattern recognition. The cuckoo finch, Anomalospiza imberbis, and its host the tawny-flanked prinia, Prinia subflava, lay highly polymorphic eggs with a great deal of variation in colour and patterning, with the cuckoo finch capable of close egg mimicry. Behavioural experiments in Zambia have previously shown that prinias use colour and multiple 'low-level' (occurring in early stages of visual processing) pattern attributes, derived from spatial frequency analysis, when rejecting foreign eggs. Here, we explore the extent to which host birds might also use 'higher-level' pattern attributes, derived from a feature detection algorithm, to make rejection decisions. Using a SIFT-based pattern recognition algorithm, NaturePatternMatch, we show that hosts are more likely to reject a foreign egg if its higher-level pattern features-which capture information about the shape and orientation of markings-differ from those of the host eggs. A revised statistical model explains about 37% variance in egg rejection behaviour, and differences in colour, low-level and higher-level pattern features all predict rejection, accounting for 42, 44 and 14% of the explained variance, respectively. Thus, higher-level pattern features provide a small but measurable improvement to the original model and may be especially useful when colour and low-level pattern features provide hosts with little information. Understanding the relative importance of low- and higher-level pattern features is a valuable goal for future work on animal coloration, especially in the contexts of mimicry, camouflage and individual recognition. This article is part of the theme issue 'The coevolutionary biology of brood parasitism: from mechanism to pattern'.

Project description:Dogs are particularly skilful during communicative interactions with humans. Dogs' abilities to use human communicative cues in cooperative contexts outcompete those of other species, and might be the result of selection pressures during domestication. Dogs also produce signals to direct the attention of humans towards outside entities, a behaviour often referred to as showing behaviour. This showing behaviour in dogs is thought to be something dogs use intentionally and referentially. However, there is currently no evidence that dogs communicate helpfully, i.e. to inform an ignorant human about a target that is of interest to the human but not to the dog. Communicating with a helpful motive is particularly interesting because it might suggest that dogs understand the human's goals and need for information. In study 1, we assessed whether dogs would abandon an object that they find interesting in favour of an object useful for their human partner, a random novel distractor, or an empty container. Results showed that it was mainly self-interest that was driving the dogs' behaviour. The dogs mainly directed their behaviour towards the object they had an interest in, but dogs were more persistent when showing the object relevant to the human, suggesting that to some extent they took the humans interest into account. Another possibility is that dogs' behaviour was driven by an egocentric motivation to interact with novel targets and that the dogs' neophila might have masked their helpful tendencies. Therefore, in study 2 the dogs had initial access to both objects, and were expected to indicate only one (relevant or distractor). The human partner interacted with the dog using vocal communication in half of the trials, and remaining silent in the other half. Dogs from both experimental groups, i.e. indicating the relevant object or indicating the distractor, established joint attention with the human. However, the human's vocal communication and the presence of the object relevant to the human increased the persistency of showing, supporting the hypothesis that the dogs understood the objects' relevance to the human. We propose two non-exclusive explanations. These results might suggest that informative motives could possibly underlie dogs' showing. It is also possible that dogs might have indicated the location of the hidden object because they recognised it as the target of the human's search. This would be consistent with taking into account the objects' relevance, without necessarily implying that the dogs understood the human's state of knowledge.

Dataset Information

Tautomers of a Fluorescent G Surrogate and Their Distinct Photophysics Provide Additional Information Channels.

Publications

Tautomers of a Fluorescent G Surrogate and Their Distinct Photophysics Provide Additional Information Channels.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets