7asa

Structural highlights

Function

RQCH_BACSU Part of the ribosome quality control system (RQC). Recruits Ala-charged tRNA and directs the elongation of stalled nascent chains on 50S ribosomal subunits, leading to non-templated C-terminal Ala extensions (Ala tail). The Ala tail promotes nascent chain degradation. Selectively binds tRNA(Ala)(UGC), which is presumably the sole source of tRNA(Ala) used for Ala tailing directed by this protein. May add between 1 and at least 8 Ala residues; detection of the Ala tail requires either deletion of clpP or its inhibition. Binds to 50S ribosomal subunits, at least 30% of which contain a P-site tRNA and thus are obstructed.^[1]

References

1. ↑ Lytvynenko I, Paternoga H, Thrun A, Balke A, Müller TA, Chiang CH, Nagler K, Tsaprailis G, Anders S, Bischofs I, Maupin-Furlow JA, Spahn CMT, Joazeiro CAP. Alanine Tails Signal Proteolysis in Bacterial Ribosome-Associated Quality Control. Cell. 2019 Jun 27;178(1):76-90.e22. PMID:31155236 doi:10.1016/j.cell.2019.05.002