9W0N
Escherichia coli transcription-translation coupled complex class B (TTC-B) that ribosome walking for 4 codons to a 9 codon mRNA spacer, and fMet-tRNAs in E-site and P-site of the ribosome
This is a non-PDB format compatible entry.
Summary for 9W0N
| Entry DOI | 10.2210/pdb9w0n/pdb |
| EMDB information | 65509 |
| Descriptor | 23S rRNA, Large ribosomal subunit protein uL6, Large ribosomal subunit protein bL9, ... (66 entities in total) |
| Functional Keywords | ribosome, rna polymerase, translation, transcription, coupling, transcription-translation coupling, expressome/ribosome |
| Biological source | Escherichia coli K-12 More |
| Total number of polymer chains | 66 |
| Total formula weight | 2779984.06 |
| Authors | |
| Primary citation | Wang, C.,Molodtsov, V.,Shandilya, S.,You, L.,Zhang, J.,Kuznedelov, K.,Nickels, B.E.,Kaelber, J.T.,Blaha, G.,Ebright, R.H. Structural basis of long-range transcription-translation coupling. Proc.Natl.Acad.Sci.USA, 123:e2528970123-e2528970123, 2026 Cited by PubMed Abstract: Structures recently have been reported of molecular assemblies that mediate transcription-translation coupling in . In these molecular assemblies, termed "coupled transcription-translation complexes" or "TTC-B," RNA polymerase (RNAP) directly interacts with the ribosome, the transcription elongation factor NusG or its paralog RfaH forms a bridge between RNAP and ribosome, and the transcription elongation factor NusA optionally forms a second bridge between RNAP and ribosome. Here, we report structures of coupled transcription-translation complexes having mRNA spacers between RNAP and ribosome longer than the maximum-length mRNA spacer compatible with formation of TTC-B. The results define a class of coupled transcription-translation complex, termed "TTC-LC," where "LC" denotes "long-range coupling." TTC-LC differs from TTC-B by a ~60° rotation and ~70 Å translation of RNAP relative to ribosome, resulting in loss of direct interactions between RNAP and ribosome and creation of a ~70 Å gap between RNAP and ribosome. TTC-LC accommodates long mRNA spacers by looping out mRNA from the gap between RNAP and ribosome. We present evidence that TTC-LC is a functional intermediate in assembling and disassembling TTC-B, mediating pre-TTC-B transcription-translation coupling before a ribosome catches up to RNAP, and mediating post-TTC-B transcription-translation coupling after a ribosome stops moving and RNAP continues moving. We show that TTC-B, but not TTC-LC, is severely defective in RNA-hairpin-dependent transcription termination, and that both TTC-B and TTC-LC are severely defective in Rho-dependent transcription termination. PubMed: 42268877DOI: 10.1073/pnas.2528970123 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.5 Å) |
Structure validation
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