TSEN2
Function
Constitutes one of the two catalytic subunit of the tRNA-splicing endonuclease complex, a complex responsible for identification and cleavage of the splice sites in pre-tRNA. It cleaves pre-tRNA at the 5'- and 3'-splice sites to release the intron. The products are an intron and two tRNA half-molecules bearing 2',3'-cyclic phosphate and 5'-OH termini. There are no conserved sequences at the splice sites, but the intron is invariably located at the same site in the gene, placing the splice sites an invariant distance from the constant structural features of the tRNA body. Isoform 1 probably carries the active site for 5'-splice site cleavage. The tRNA splicing endonuclease is also involved in mRNA processing via its association with pre-mRNA 3'-end processing factors, establishing a link between pre-tRNA splicing and pre-mRNA 3'-end formation, suggesting that the endonuclease subunits function in multiple RNA-processing events. Isoform 2 is responsible for processing a yet unknown RNA substrate. The complex containing isoform 2 is not able to cleave pre-tRNAs properly, although it retains endonucleolytic activity.
Involvement in disease
Pontocerebellar hypoplasia 2B
PCH2B
A disorder characterized by an abnormally small cerebellum and brainstem, and progressive microcephaly from birth combined with extrapyramidal dyskinesia. Severe chorea occurs and epilepsy is frequent. There are no signs of spinal cord anterior horn cells degeneration.
None
The disease is caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the tRNA-intron endonuclease family.
Tissue Specificity
Isoform 1 and isoform 2 are widely expressed at very low level.
Cellular localization
- Nucleus
- Nucleus
- Nucleolus
- May be transiently localized in the nucleolus.
Alternative names
SEN2, TSEN2, tRNA-splicing endonuclease subunit Sen2, tRNA-intron endonuclease Sen2, HsSen2