RESUMO
A novel cyclin, CycJ18, was isolated by complementation of G1 cyclin-deficient budding yeast with an Arabidopsis cDNA library. CycJ18 shares only 20% identity in its conserved cyclin box domain with other cyclins, and is predominantly expressed in young seedlings. CycJ18 is a member of a potential new plant cyclin class.
Assuntos
Arabidopsis/metabolismo , Ciclinas/isolamento & purificação , Proteínas de Plantas/isolamento & purificação , Sequência de Aminoácidos , Ciclinas/genética , Biblioteca Gênica , Teste de Complementação Genética , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/genética , Alinhamento de SequênciaRESUMO
Sequences of the alpha1, alpha2 and theta globin genes from six equid species have been determined to investigate relationships within the genus Equus. Analyses using standard phylogenetic methods, or an approach designed to account for the effects of gene conversion between the alpha genes, gave broadly similar results and show that the horses diverged from the zebra/ass ancestor approximately 2.4 million years ago and that the zebra and ass species arose in a rapid radiation approximately 0.9 million years ago. These results from the alpha genes are corroborated by theta gene data and are in contrast to mitochondrial DNA studies of the phylogeny of this genus, which suggest a more gradual set of speciation events.
Assuntos
Equidae/genética , Evolução Molecular , Globinas/genética , Cavalos/genética , Animais , Sequência de Bases , DNA/genética , Primers do DNA/genética , Conversão Gênica , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Fatores de TempoRESUMO
Variation in the control region and the 12S rRNA gene of all surviving mitochondrial lineages of Przewalski's horse was investigated. Variation is low despite the present day population being descended from 13 individuals probably representing animals from three different regions of its range. Phylogenetic comparison of these sequences, with sequences for the domestic horse, does not resolve the ancestral status of either horse.
Assuntos
DNA Mitocondrial/genética , Variação Genética , Cavalos/genética , RNA Ribossômico/genética , Animais , Feminino , Masculino , LinhagemRESUMO
The alpha-globin gene complex in Equus caballus has been mapped by fluorescence in situ hybridization to the telomeric region of the long arm of chromosome 13. This is the first equine gene to be mapped to this chromosome.
