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1.
Nat Commun ; 10(1): 4077, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501432

RESUMO

Climatic conditions changing over time and space shape the evolution of organisms at multiple levels, including temperate lizards in the family Lacertidae. Here we reconstruct a dated phylogenetic tree of 262 lacertid species based on a supermatrix relying on novel phylogenomic datasets and fossil calibrations. Diversification of lacertids was accompanied by an increasing disparity among occupied bioclimatic niches, especially in the last 10 Ma, during a period of progressive global cooling. Temperate species also underwent a genome-wide slowdown in molecular substitution rates compared to tropical and desert-adapted lacertids. Evaporative water loss and preferred temperature are correlated with bioclimatic parameters, indicating physiological adaptations to climate. Tropical, but also some populations of cool-adapted species experience maximum temperatures close to their preferred temperatures. We hypothesize these species-specific physiological preferences may constitute a handicap to prevail under rapid global warming, and contribute to explaining local lizard extinctions in cool and humid climates.


Assuntos
Meio Ambiente , Variação Genética , Genoma , Lagartos/genética , Lagartos/fisiologia , Temperatura , Animais , Regulação da Temperatura Corporal/fisiologia , Clima , Evolução Molecular , Filogenia
2.
Toxins (Basel) ; 10(1)2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29301241

RESUMO

The Nose-horned Viper (Vipera ammodytes) is one of the most widespread and venomous snakes in Europe, which causes high frequent snakebite accidents. The first comprehensive venom characterization of the regional endemic Transcaucasian Nose-horned Viper (Vipera ammodytes transcaucasiana) and the Transdanubian Sand Viper (Vipera ammodytes montandoni) is reported employing a combination of intact mass profiling and bottom-up proteomics. The bottom-up analysis of both subspecies identified the major snake protein families of viper venoms. Furthermore, intact mass profiling revealed the presence of two tripeptidic metalloprotease inhibitors and their precursors. While previous reports applied multivariate analysis techniques to clarify the taxonomic status of the subspecies, an accurate classification of Vipera ammodytestranscaucasiana is still part of the ongoing research. The comparative analysis of the viper venoms on the proteome level reveals a close relationship between the Vipera ammodytes subspecies, which could be considered to clarify the classification of the Transcaucasian Nose-horned Viper. However, the slightly different ratio of some venom components could be indicating interspecific variations of the two studied subspecies or intraspecies alternations based on small sample size. Additionally, we performed a bioactivity screening with the crude venoms against several human cancerous and non-cancerous cell lines, which showed interesting results against a human breast adenocarcinoma epithelial cell line. Several fractions of Vipera a. transcaucasiana demonstrated a strong cytotoxic effect on triple negative MDA MB 231 breast cancer cells.


Assuntos
Venenos de Víboras/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Proteoma , Proteínas de Répteis/análise , Proteínas de Répteis/farmacologia , Turquia , Venenos de Víboras/farmacologia , Viperidae
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