Data/hora: 18/06/2024 17:43:52

Provedor de dados: 	74	
País: 	Brazil	
Título: 	Purine and pyrimidine composition in 5S rRNA and its mutational significance	
Autores: 	Subacius,Sandra Maria Rodrigues; Bussab,Wilton de Oliveira.	
Data: 	1998-06-01	
Ano: 	1998	
Resumo: 	Variations observed in 5S rRNA base compositions are almost entirely due to fixation of point mutations. As a consequence, 5S rRNA size has remained relatively constant during evolution and, therefore, dependencies among the four bases can be predicted. In order to characterize the nature and to determine the degree of such dependencies, correlation analysis followed by principal component factorial analysis was conducted on a large sample of 5S rRNA sequences. The results show that the purine and pyrimidine contents tend to remain constant, so that A + G = Kpur and C + U = Kpyr. The composition of the four bases expressed now by Kpur/Kpyr relationships is also constant (Ks). These relationships imply that the behavior of the mutations in the variable sites of the molecule follows rules imposed by the chemical nature of the bases involved. Consequently, transition mutations would be more favored than substitutions in transversion sites and also than insertion-deletion (rare in 5S rRNAs), since transitions would not significantly alter the values of the Ks-index.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000200014	
Editor: 	Sociedade Brasileira de Genética	
Relação: 	10.1590/S1415-47571998000200014	
Formato: 	text/html	
Fonte: 	Genetics and Molecular Biology  v.21 n.2 1998	
Fonte: 	info:eu-repo/semantics/openAccess