RESUMO
Cytological analysis of a squirrel monkey indicates a considerable degree of chromosomal polymorphism. DNA synthetic patterns reveal late synthesis in chromosomal segments that are C-band negative and asynchrony in DNA replication between homologs. Location of a satellite DNA with a CsCl neutral buoyant density of 4.691 g/ml was mainly in the noncentromeric constitutive heterochromatin.
Assuntos
Cromossomos , Replicação do DNA , DNA Satélite , DNA , Haplorrinos/metabolismo , Saimiri/metabolismo , Animais , DNA/análise , DNA/biossíntese , DNA Satélite/análise , Genes , Masculino , Hibridização de Ácido Nucleico , Polimorfismo GenéticoRESUMO
A specific class of DNA sequences, the inverted repetitive sequences, forms hairpin-like structures in denatured DNA by the folding back of a single linear chain. The reassociation process of these sequences is unimolecular and the rate is extremely fast. Inverted repetitive sequences comprise 6% of the total human genome. They appear to be heterogeneous in length with an overall average length of 190 nucleotides. The inverted sequences are represented in almost all families of repetition frequencies, highly repetitive as well as very few copies per genome. They are not localized at unique sites on metaphase chromosomes. It is estimated that there are approximately 2 X 10(6) inverted repeats per haploid human genome. The biological function of this class of sequences is unknown.
Assuntos
DNA de Neoplasias , Genes , Sequência de Bases , Cromossomos , Genética Médica , Células HeLa , Temperatura Alta , Humanos , Cinética , Linfócitos , Peso Molecular , Mutação , Conformação de Ácido Nucleico , Desnaturação de Ácido Nucleico , Hibridização de Ácido NucleicoRESUMO
Human DNA contains 35 percent repetitive and 65 percent nonrepetitive sequences. Eight satellite DNAs have now been identified in human DNA. The highly repetitive non-satellite sequences are arranged in blocks 1,100 nucleotides long and interspersed with intermediate repetitive and nonrepetitive sequences greater than 2,500 nucleotides long. Approximately 2.5-3.9 percent of the nonrepetitive sequences are represented in total cellular RNA of normal and leukemic leukocytes.
