Article · Wikipedia archive · Last revised Jun 7, 2026

RNAI

RNAI is a non-coding RNA that is an antisense repressor of the replication of some E. coli plasmids, including ColE1. Plasmid replication is usually initiated by RNAII, which acts as a primer by binding to its template DNA. The complementary RNAI binds RNAII prohibiting it from its initiation role. The rate of degradation of RNAI is therefore a major factor in the control of plasmid replication. This rate of degradation is aided by the pcnB gene product, which polyadenylates the 3' end of RNAI targeting it for degradation by PNPase.

Last revised
Jun 7, 2026
Read time
≈ 1 min
Length
263 w
Citations
3
Source
RNAI
Identifiers
SymbolRNAI
RfamRF00106
Other data
RNA typeGene; antisense
DomainBacteria
SOSO:0000644
PDB structuresPDBe

RNAI is a non-coding RNA that is an antisense repressor of the replication of some E. coli plasmids, including ColE1. Plasmid replication is usually initiated by RNAII,1 which acts as a primer by binding to its template DNA. The complementary RNAI binds RNAII prohibiting it from its initiation role. The rate of degradation of RNAI is therefore a major factor in the control of plasmid replication. This rate of degradation is aided by the pcnB (plasmid copy number B) gene product,2 which polyadenylates the 3' end of RNAI targeting it for degradation by PNPase.3

References

References

  1. Masukata H, Tomizawa J (January 1986). "Control of primer formation for ColE1 plasmid replication: conformational change of the primer transcript". Cell. 44 (1): 125–136. doi:10.1016/0092-8674(86)90491-5. PMID 2416472. S2CID 400406.
  2. He L, Söderbom F, Wagner EG, Binnie U, Binns N, Masters M (September 1993). "PcnB is required for the rapid degradation of RNAI, the antisense RNA that controls the copy number of ColE1-related plasmids". Molecular Microbiology. 9 (6): 1131–1142. doi:10.1111/j.1365-2958.1993.tb01243.x. PMID 7523833. S2CID 38698693.
  3. Xu F, Lin-Chao S, Cohen SN (July 1993). "The Escherichia coli pcnB gene promotes adenylylation of antisense RNAI of ColE1-type plasmids in vivo and degradation of RNAI decay intermediates". Proceedings of the National Academy of Sciences of the United States of America. 90 (14): 6756–6760. Bibcode:1993PNAS...90.6756X. doi:10.1073/pnas.90.14.6756. PMC 47011. PMID 7688127.
Further reading

Further reading

External links