Published September 1981 | Version v1
Journal article

A poly (U) polymerase in ribosome preparations from Ehrlich ascites tumor cells

  • 1. UNESP, Botucatu (Brazil). Inst. Basico de Biologia Medica e Agricola
  • 2. Texas Univ., Austin (USA). Cell Research Institute

Description

A ribosome-bound poly (U) polymerase from Ehrlich ascites tumor cells is partially characterized. It adds UMPs to RNAs terminating in U-(3')-OH. The UMP-rich segments added reach average sizes of up to 18 nucleotides. CTP is strongly inhibitory to the enzyme. The main endogenous primers are low molecular weight RNAs which are found, after the addition of UMPs, mostly in the 6-8 S range. Some evidence suggests that a 5 S rRNA or polysome-associated 7 S RNA could be the main endogenous primers. (Author)

Abstract (Portuguese)

Apresenta-se a caracterizacao parcial de uma poli (U) polimerase ligada a ribossomos de celulas do tumor ascitico de Ehrlich. A enzima adiciona UMPs a RNAs terminados em U-(3')-OH. Os segmentos ricos em UMP adicionados alcancam tamanhos medios de ate 18 nucleotidios. CTP e um forte inibidor da enzima. Os iniciadores endogenos principais sao RNAs de baixo peso molecular. Estes sao encontrados, apos a adicao dos UMPs, predominantemente na regiao 6-8S. Alguma evidencia sugere que os iniciadores endogenos principais poderiam ser o rRna 5S ou o RNA 7S associado a polirribossomos. (Autor)

Additional details

Publishing Information

Journal Title
Rev. Bras. Genet.
Journal Volume
4
Journal Issue
3
Series
Rev. Bras. Genet.
Journal Page Range
245-268
ISSN
0100-8455