title: The question remains: is the spliceosome a ribozyme?
abstract: The two phosphoryl transfer steps of pre-mRNA splicing are catalyzed within the large ribonuclear protein machine called the spliceosome. The highly dynamic nature of the spliceosome has presented many challenges to a structural and mechanistic understanding of its catalytic core. While much evidence supports the popular hypothesis that the catalytic steps of pre-mRNA splicing are mediated by spliceosomal RNA, a role for protein in catalysis cannot yet be ruled out. A highly conserved protein, Prp8, is a component of the catalytic core. We review data consistent with the hypothesis that Prp8 functions as a cofactor to an RNA enzyme.
authors.affiliation: Graduate Group in Biophysics, University of California, San Francisco, San Francisco, California 94143-0448, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Collins
authors.forename: C
authors.initials: C
authors.lastname: Guthrie
mesh_terms: D002384:Catalysis; D020134:Catalytic Domain; D012322:RNA Precursors / Q000378:metabolism; D012326:RNA Splicing; D016337:RNA, Catalytic / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D017381:Spliceosomes / Q000378:metabolism*
chemical_list: D012322:RNA Precursors; D016337:RNA, Catalytic; D012333:RNA, Messenger