Journal article

Essential Role of a Trypanosome U4-Specific Sm Core Protein in Small Nuclear Ribonucleoprotein Assembly and Splicing


Authors listJae, N; Wang, PP; Gu, TP; Hühn, M; Palfi, Z; Urlaub, H; Bindereif, A

Publication year2010

Pages379-386

JournalEukaryotic Cell

Volume number9

Issue number3

ISSN1535-9778

eISSN1535-9786

Open access statusGold

DOI Linkhttps://doi.org/10.1128/EC.00353-09

PublisherAmerican Society for Microbiology


Abstract
Spliceosomal small nuclear ribonucleoproteins (snRNPs) in trypanosomes contain either the canonical heptameric Sm ring or variant Sm cores with snRNA-specific Sm subunits. Here we show biochemically by a combination of RNase H cleavage and tandem affinity purification that the U4 snRNP contains a variant Sm heteroheptamer core in which only SmD3 is replaced by SSm4. This U4-specific, nuclear-localized Sm core protein is essential for growth and splicing. As shown by RNA interference (RNAi) knockdown, SSm4 is specifically required for the integrity of the U4 snRNA and the U4/U6 di-snRNP in trypanosomes. In addition, we demonstrate by in vitro reconstitution of Sm cores that under stringent conditions, the SSm4 protein suffices to specify the assembly of U4 Sm cores. Together, these data indicate that the assembly of the U4-specific Sm core provides an essential step in U4/U6 di-snRNP biogenesis and splicing in trypanosomes.



Citation Styles

Harvard Citation styleJae, N., Wang, P., Gu, T., Hühn, M., Palfi, Z., Urlaub, H., et al. (2010) Essential Role of a Trypanosome U4-Specific Sm Core Protein in Small Nuclear Ribonucleoprotein Assembly and Splicing, Eukaryotic Cell, 9(3), pp. 379-386. https://doi.org/10.1128/EC.00353-09

APA Citation styleJae, N., Wang, P., Gu, T., Hühn, M., Palfi, Z., Urlaub, H., & Bindereif, A. (2010). Essential Role of a Trypanosome U4-Specific Sm Core Protein in Small Nuclear Ribonucleoprotein Assembly and Splicing. Eukaryotic Cell. 9(3), 379-386. https://doi.org/10.1128/EC.00353-09


Last updated on 2025-10-06 at 09:54