RESUMO
Genes located on the mammalian Y chromosome outside of the pseudoautosomal region do not recombine with those on the X and are predicted to either undergo selection for male function or gradually degenerate because of an accumulation of deleterious mutations. Here, phylogenetic analyses of X-Y homologues, Zfx and Zfy, among 26 felid species indicate two ancestral episodes of directed genetic exchange (ectopic gene conversion) from X to Y: once during the evolution of pallas cat and once in a common predecessor of ocelot lineage species. Replacement of the more rapidly evolving Y homologue with the evolutionarily constrained X copy may represent a mechanism for adaptive editing of functional genes on the nonrecombining region of the mammalian Y chromosome.
Assuntos
Carnívoros/classificação , Carnívoros/genética , Gatos/genética , Conversão Gênica , Filogenia , Cromossomo X , Cromossomo Y , Animais , Sequência de Bases , Mapeamento Cromossômico , Primers do DNA , Éxons , Feminino , Masculino , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , Recombinação Genética , Seleção Genética , Dedos de Zinco/genéticaRESUMO
Synthetic deoxyoligonucleotides have been 5'-aminoalkylated at the end of step-wise synthesis on the polymer support. This was achieved through the activation of the 5'-hydroxyl group as its 5'-imidazolyl derivative using carbonyldiimidazole, which was subsequently displaced with hexamethylene diamine to yield the title compound. The alkyl carbamate linkage thus generated withstands the deprotection conditions used in oligonucleotide synthesis. Purification by gel electrophoresis and further derivatization at the 5'-amino group with N-hydroxysuccinimidobiotin is described.
