What is the clinical evidence from this study?

Study design: Other. Population: Poliovirus infection. Intervention: Poliovirus infection vs. Uninfected HeLa cell RNA. Primary outcome: Presence of 5'-terminal m7G(5')ppp(5')Np capping group.

February 1, 1976Proceedings of the National Academy of Sciences277 citationsOpen Access

The 5' end of poliovirus mRNA is not capped with m7G(5')ppp(5')Np.

ANAkio NomotoTokyo Medical and Dental University YLY F LeeTaiwan Livestock Research Institute EWEckard WimmerCalifornia Institute of Technology

Key Result

Poliovirus mRNA lacks the 5'-terminal m7G(5')ppp(5')Np capping group, indicating it is not involved in poliovirus protein synthesis.

Structured PICO

Population

In vitro study analyzing the 5' terminal structure of mRNA from poliovirus-infected HeLa cells.

Intervention

Growth in the presence of phosphorus-32 and actinomycin D

Comparator

Total cytoplasmic [32P]RNA of HeLa cells

Outcome

Presence of 5'-terminal m7G(5')ppp(5')Np capping groupsurrogate

Demonstrates that poliovirus mRNA lacks the typical 5' cap structure found in host cellular mRNA.

Limitations

The exact nature of the 5' end of the poliovirus genome remains puzzling and requires further investigation.

Abstract

Poliovirus was grown in HeLa cells in the presence of phosphorus-32 and actinomycin D. Three to four hours after infection, viral mRNA was recovered from polyribosomes and its identity verified by two-dimensional gel electrophoresis of RNase T1 digests. Digestion of the viral 32PmRNA with RNase T2 and separation of the products by ion exchange chromatography at pH 5 yielded pUp as possible 5' terminus but no "capping group" of the structure m7G(5')ppp(5')Np. Total cytoplasmic 32PRNA of HeLa cells, on the other hand, was found to contain capping groups. Neither the capping group nor ppNp or pppNp was found in an RNase T2 digest of poliovirion 32PRNA, in agreement with previous results Wimmer, E. (1972) J. Mol. Biol. 68, 537-540. The data indicate that 5'-terminal m7G(5')ppp(5')Np is absent from poliovirus RNAs and, therefore, is not involved in poliovirus protein synthesis.

Ask AI

Helpful

Bookmark

View Full Paper