Sen15 is a small, conserved noncatalytic subunit of the heterotetrameric tRNA-splicing endonuclease complex. Together with Sen2, Sen34 and Sen54 it supports recognition and excision of introns from precursor tRNAs before the cleaved exons are ligated. The catalytic splice-site cleavage centers reside in Sen2 and Sen34. Nuclear and cytosolic pools have been reported in fission yeast localization screens.
Summary: tRNA-intron endonuclease complex is supported.
Reason: The target is a SEN15-family protein, supporting transfer of the characterized four-subunit tRNA-splicing endonuclease role. SEN2 and SEN34 encode the cleavage active sites; Sen15 is a noncatalytic participant in intron recognition/excision. Participation in the overall cleavage-and-ligation pathway does not assert that Sen15 ligates RNA.
Our results demonstrate that the eucaryal tRNA splicing endonuclease contains two functionally independent active sites for cleavage of the 5' and 3' splice sites, encoded by SEN2 and SEN34, respectively.
Summary: tRNA-intron endonuclease complex is supported.
Reason: The target is a SEN15-family protein, supporting transfer of the characterized four-subunit tRNA-splicing endonuclease role. SEN2 and SEN34 encode the cleavage active sites; Sen15 is a noncatalytic participant in intron recognition/excision. Participation in the overall cleavage-and-ligation pathway does not assert that Sen15 ligates RNA.
Our results demonstrate that the eucaryal tRNA splicing endonuclease contains two functionally independent active sites for cleavage of the 5' and 3' splice sites, encoded by SEN2 and SEN34, respectively.
GO:0000379 tRNA-type intron splice site recognition and cleavage
IBA GO_REF:0000033
ACCEPT
Summary: tRNA-type intron splice site recognition and cleavage is supported.
Reason: The target is a SEN15-family protein, supporting transfer of the characterized four-subunit tRNA-splicing endonuclease role. SEN2 and SEN34 encode the cleavage active sites; Sen15 is a noncatalytic participant in intron recognition/excision. Participation in the overall cleavage-and-ligation pathway does not assert that Sen15 ligates RNA.
Our results demonstrate that the eucaryal tRNA splicing endonuclease contains two functionally independent active sites for cleavage of the 5' and 3' splice sites, encoded by SEN2 and SEN34, respectively.
GO:0000379 tRNA-type intron splice site recognition and cleavage
IEA GO_REF:0000002
ACCEPT
Summary: tRNA-type intron splice site recognition and cleavage is supported.
Reason: The target is a SEN15-family protein, supporting transfer of the characterized four-subunit tRNA-splicing endonuclease role. SEN2 and SEN34 encode the cleavage active sites; Sen15 is a noncatalytic participant in intron recognition/excision. Participation in the overall cleavage-and-ligation pathway does not assert that Sen15 ligates RNA.
Our results demonstrate that the eucaryal tRNA splicing endonuclease contains two functionally independent active sites for cleavage of the 5' and 3' splice sites, encoded by SEN2 and SEN34, respectively.
Summary: nucleic acid binding is not fully resolved.
Reason: The Sen15 subunit supports an RNA-processing complex, but specific RNA contacts by the target or conserved contacts in a characterized Sen15 ortholog have not been established in the primary evidence inspected here. Complex membership alone does not resolve whether this particular subunit binds nucleic acid. Binding within an assembled complex would be sufficient; an isolated-subunit assay is not required.
Our results demonstrate that the eucaryal tRNA splicing endonuclease contains two functionally independent active sites for cleavage of the 5' and 3' splice sites, encoded by SEN2 and SEN34, respectively.
HDA PMID:16823372 ORFeome cloning and global analysis of protein localization ...
KEEP AS NON CORE
Summary: nucleus is retained as an ancillary annotation.
Reason: Retain the PomBase localization observation from the fission yeast tagged-ORFeome screen. The accessible abstract documents the assay but not the individual localization image; the screen is not sufficient to identify which detected pool executes tRNA cleavage.
Next, we determined the localization of 4,431 proteins, corresponding to approximately 90% of the fission yeast proteome, by tagging each ORF with the yellow fluorescent protein.
HDA PMID:16823372 ORFeome cloning and global analysis of protein localization ...
KEEP AS NON CORE
Summary: cytosol is retained as an ancillary annotation.
Reason: Retain the PomBase localization observation from the fission yeast tagged-ORFeome screen. The accessible abstract documents the assay but not the individual localization image; the screen is not sufficient to identify which detected pool executes tRNA cleavage.
Next, we determined the localization of 4,431 proteins, corresponding to approximately 90% of the fission yeast proteome, by tagging each ORF with the yellow fluorescent protein.
GO:0006388 tRNA splicing, via endonucleolytic cleavage and ligation
IEA GO_REF:0000002
ACCEPT
Summary: tRNA splicing, via endonucleolytic cleavage and ligation is supported.
Reason: The target is a SEN15-family protein, supporting transfer of the characterized four-subunit tRNA-splicing endonuclease role. SEN2 and SEN34 encode the cleavage active sites; Sen15 is a noncatalytic participant in intron recognition/excision. Participation in the overall cleavage-and-ligation pathway does not assert that Sen15 ligates RNA.
Our results demonstrate that the eucaryal tRNA splicing endonuclease contains two functionally independent active sites for cleavage of the 5' and 3' splice sites, encoded by SEN2 and SEN34, respectively.
Core Functions
Conserved noncatalytic participant in the tRNA-splicing endonuclease complex, supporting splice-site recognition and intron excision.
Our results demonstrate that the eucaryal tRNA splicing endonuclease contains two functionally independent active sites for cleavage of the 5' and 3' splice sites, encoded by SEN2 and SEN34, respectively.
These computational predictions are reviewed separately from the GOA annotation set used for this review. The assessments below are from this project and do not constitute official GO annotations or endorsement by GO/UniProt. They are not included in the existing annotation review above.
Sen15 participates noncatalytically in the tRNA-splicing endonuclease complex. The predicted tRNA-splicing process is correct and already established by curated annotations and conserved-family evidence.
Review rationale: The SEN15-family assignment of the target and the PAINT-curated endonuclease-complex and splice-site-recognition assertions support a conserved noncatalytic role in pre-tRNA intron excision. The characterized budding yeast complex contains four subunits, with cleavage active sites in Sen2 and Sen34. Participation in the full splicing process does not require Sen15 itself to catalyze either cleavage or ligation. This exact process is already in GOA, and the corresponding endonuclease-participation biology is established, so the supported prediction is not novel.
Supporting Evidence:
PMID:9200603: "Our results demonstrate that the eucaryal tRNA splicing endonuclease contains two functionally independent active sites for cleavage of the 5' and 3' splice sites, encoded by SEN2 and SEN34, respectively."