FEATURES

FAMILY

DESCRIPTION

Also known as SEN2_HUMAN, TSEN2, SEN2. 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. tRNA splicing endonuclease is a heterotetramer composed of isoform 1 of TSEN2, TSEN15, TSEN34/LENG5 and TSEN54. tRNA splicing endonuclease complex also contains proteins of the pre-mRNA 3'-end processing machinery such as CLP1, CPSF1, CPSF4 and CSTF2. Isoform 2 belongs to a different complex that contains TSEN54 but low level of TSEN15 and TSEN34/LENG5.

EXTERNAL LINKS

TSEN2

tRNA-splicing endonuclease subunit Sen2

TSEN2

Molecular Synopsis