2024-03-19T04:42:11Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/400962021-06-10T12:26:04Zcom_10261_79com_10261_1col_10261_332
00925njm 22002777a 4500
dc
Nuez, Beatriz
author
Rojo, Fernando
author
Salas, Margarita
author
1992-12-01
Transcription from the late promoter, PA3, of Bacillus subtilis phage phi 29 is activated by the viral regulatory protein p4. A kinetic analysis of the activation process has revealed that the role of protein p4 is to stabilize the binding of RNA polymerase to the promoter as a closed complex without significantly affecting further steps of the initiation process. Electrophoretic band-shift assays performed with a DNA fragment spanning only the protein p4 binding site showed that RNA polymerase could efficiently retard the complex formed by protein p4 bound to the DNA. Similarly, when a DNA fragment containing only the RNA polymerase-binding region of PA3 was used, p4 greatly stimulated the binding of RNA polymerase to the DNA. These results strongly suggest that p4 and RNA polymerase contact each other at the PA3 promoter. In the light of current knowledge of the p4 activation mechanism, we propose that direct contacts between the two proteins participate in the activation process.
Proceedings of the National Academy of Sciences of the USA 89 (23) 11401-11405 (1992)
1091-6490
http://hdl.handle.net/10261/40096
http://dx.doi.org/10.13039/100000002
http://dx.doi.org/10.13039/501100003329
http://dx.doi.org/10.13039/100008054
Phage phi 29 regulatory protein p4 stabilizes the binding of the RNA polymerase to the late promoter in a process involving direct protein-protein contacts