<i>RPC82</i> Encodes the Highly Conserved, Third-Largest Subunit of RNA Polymerase Q (III) from <i>Saccharomyces cerevisiae</i>

Chiannilkulchai, Nuchanard; Stalder, Rolf; Riva, Michel; Carles, Christophe; Werner, Michel; Sentenac, André

doi:10.1128/mcb.12.10.4433-4440.1992

Cited by 19 publications

(1 citation statement)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Mutations affecting RNAPI function or deletion of rDNA from yeast cells resulted in Rpa190 nucleolar mislocalization [51]. RPO31 and RPC82 encode for DNA‐directed RNA polymerase III subunit RPC1 (Rpc160) protein, the largest subunit of RNAPIII, and the third‐largest subunit DNA‐directed RNA polymerase III subunit RPC3 (Rpc82) protein, respectively, both important for the assembly of the RNAPIII complex to promote tRNA transcription [49,52,53]. Rpc82 has been used as marker to evaluate nuclear import of RNAPIII in yeast mutant cells [54,55].…”

Section: Resultsmentioning

confidence: 99%

Translation initiation factor eIF1A rescues hygromycin B sensitivity caused by deleting the carboxy‐terminal tail in the GPN‐loop GTPase Npa3

Félix‐Pérez,

Mora‐García,

Rebolloso‐Gómez

et al. 2024

The FEBS Journal

View full text Add to dashboard Cite

The essential yeast protein GPN‐loop GTPase 1 (Npa3) plays a critical role in RNA polymerase II (RNAPII) assembly and subsequent nuclear import. We previously identified a synthetic lethal interaction between a mutant lacking the carboxy‐terminal 106‐amino acid tail of Npa3 (npa3ΔC) and a bud27Δ mutant. As the prefoldin‐like Bud27 protein participates in ribosome biogenesis and translation, we hypothesized that Npa3 may also regulate these biological processes. We investigated this proposal by using Saccharomyces cerevisiae strains episomally expressing either wild‐type Npa3 or hypomorphic mutants (Npa3ΔC, Npa3K16R, and Npa3G70A). The Npa3ΔC mutant fully supports RNAPII nuclear localization and activity. However, the Npa3K16R and Npa3G70A mutants only partially mediate RNAPII nuclear targeting and exhibit a higher reduction in Npa3 function. Cell proliferation in these strains displayed an increased sensitivity to protein synthesis inhibitors hygromycin B and geneticin/G418 (npa3G70A > npa3K16R > npa3ΔC > NPA3 cells) but not to transcriptional elongation inhibitors 6‐azauracil, mycophenolic acid or 1,10‐phenanthroline. In all three mutant strains, the increase in sensitivity to both aminoglycoside antibiotics was totally rescued by expressing NPA3. Protein synthesis, visualized by quantifying puromycin incorporation into nascent‐polypeptide chains, was markedly more sensitive to hygromycin B inhibition in npa3ΔC, npa3K16R, and npa3G70A than NPA3 cells. Notably, high‐copy expression of the TIF11 gene, that encodes the eukaryotic translation initiation factor 1A (eIF1A) protein, completely suppressed both phenotypes (of reduced basal cell growth and increased sensitivity to hygromycin B) in npa3ΔC cells but not npa3K16R or npa3G70A cells. We conclude that Npa3 plays a critical RNAPII‐independent and previously unrecognized role in translation initiation.

show abstract

Section: Resultsmentioning

confidence: 99%

Translation initiation factor eIF1A rescues hygromycin B sensitivity caused by deleting the carboxy‐terminal tail in the GPN‐loop GTPase Npa3

Félix‐Pérez,

Mora‐García,

Rebolloso‐Gómez

et al. 2024

The FEBS Journal

View full text Add to dashboard Cite

show abstract

A mutation in the C31 subunit of Saccharomyces cerevisiae RNA polymerase III affects transcription initiation.

et al. 1995

View full text Add to dashboard Cite

The C31 subunit belongs to a complex of three subunits (C31, C34 and C82) specific to RNA polymerase (pol) III that have no counterparts in other RNA polymerases. This complex is thought to play a role in transcription initiation since it interacts with the general initiation factor TFIIIB via subunit C34. We have obtained a conditional mutation of pol III by partially deleting the acidic C‐terminus of the C31 subunit. A Saccharomyces cerevisiae strain carrying this truncated C31 subunit is impaired in in vivo transcription of tRNAs and failed to grow at 37 degrees C. This conditional growth phenotype was suppressed by overexpression of the gene coding for the largest subunit of pol III (C160), suggesting an interaction between C160 and C31. The mutant pol III enzyme transcribed non‐specific templates at wild‐type rates in vitro, but was impaired in its capacity to transcribe tRNA genes in the presence of general initiation factors. Transcription initiation, but not termination or recycling of the enzyme, was affected in the mutant, suggesting that it could be altered on interaction with initiation factors or on the formation of the open complex. Interestingly, the C‐terminal deletion was also suppressed by a high gene dosage of the DED1 gene encoding a putative helicase.

show abstract

A general suppressor of RNA polymerase I, II and III mutations in Saccharomyces cerevisiae

et al. 1993

View full text Add to dashboard Cite

RPC82 Encodes the Highly Conserved, Third-Largest Subunit of RNA Polymerase Q (III) from Saccharomyces cerevisiae

Cited by 19 publications

References 45 publications

Translation initiation factor eIF1A rescues hygromycin B sensitivity caused by deleting the carboxy‐terminal tail in the GPN‐loop GTPase Npa3

Translation initiation factor eIF1A rescues hygromycin B sensitivity caused by deleting the carboxy‐terminal tail in the GPN‐loop GTPase Npa3

A mutation in the C31 subunit of Saccharomyces cerevisiae RNA polymerase III affects transcription initiation.

A general suppressor of RNA polymerase I, II and III mutations in Saccharomyces cerevisiae

Contact Info

Product

Resources

About