Ro60 ribonucleoprotein inhibits transcription by T3 RNA polymerase in vitro.
BACKGROUND
Ro60 ribonucleoprotein is a conserved molecule belonging to the family of Ro ribonucleoproteins and targeted by autoantibodies produced in patients with systemic lupus erythematosus or Sjogren's syndrome. Ro60 plays a role in postranscription events, as well as in the nucleocytoplasmic shuttling of RNA polymerase III transcripts.


OBJECTIVE
To evaluate the in vitro effects of Ro60 on T3 RNA polymerase transcription.


METHODS
Ro60 ribonucleoprotein was affinity-purified from human spleen extracts using 4B-Sepharose linked to anti-Ro60 monoclonal antibodies. Purified Ro60 was incorporated into the T3 RNA polymerase transcription reaction system using pTRI-beta-Actin-human DNA as a template.


RESULTS
Ro60 inhibited initiation of the transcription process in a dose-dependent manner; neither elongation nor termination was affected by Ro.


CONCLUSIONS
In vitro, Ro60 appears to inhibit the transcription of a T3 RNA polymerase-dependent template.
Campos-Almaraz
M D
MD
Department of Molecular Biology and Immunotechnology, Universidad Autonoma de Zacatecas, Guadalupe, Mexico.
Barbosa-Cisneros
O
O
Herrera-Esparza
R
R
D000328:Adult; D001324:Autoantigens / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D015153:Blotting, Western; D002478:Cells, Cultured; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008297:Male; D020733:RNA, Small Cytoplasmic; D012016:Reference Values; D012261:Ribonucleoproteins / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D012680:Sensitivity and Specificity; D013154:Spleen / Q000737:chemistry / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects / Q000502:physiology*; D000099207:SS-A Antigen
D001324:Autoantigens; D012321:DNA-Directed RNA Polymerases; D020733:RNA, Small Cytoplasmic; D012261:Ribonucleoproteins; D000099207:SS-A Antigen; C116006:RO60 protein, human; C081591:bacteriophage T3 RNA polymerase