A 10 residue motif at the C-terminus of the RNA pol II CTD is required for transcription, splicing and 3' end processing.
The RNA polymerase II C-terminal heptad repeat domain (CTD) is essential for normal transcription and co-transcriptional processing of mRNA precursors. The mammalian CTD comprises 52 heptads whose consensus, YSPTSPS, is conserved throughout eukaryotes, followed by a 10 amino acid C-terminal sequence that is conserved only among vertebrates. Here we show that surprisingly, the heptad repeats are not sufficient to support efficient transcription, pre-mRNA processing or full cell viability. In addition to the heptads, the 10 amino acid C-terminal motif is essential for high level transcription, splicing and poly(A) site cleavage. Efficient mRNA synthesis from a transiently transfected reporter gene required the C-terminal motif plus between 16 and 25 heptad repeats from either the N- or C-terminal half of the CTD. Twenty-seven consensus heptads plus the C-terminal motif also supported efficient mRNA synthesis but not cell viability.
Fong
Nova
N
Department of Biochemistry and Molecular Genetics, UCHSC, B121, 4200 E. 9th Avenue, Denver, CO 80262, USA.
Bird
Gregory
G
Vigneron
Marc
M
Bentley
David L
DL
D020816:Amino Acid Motifs; D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000235:genetics; D017930:Genes, Reporter; D009154:Mutation; D009865:Oocytes / Q000166:cytology / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012319:RNA Polymerase II / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012322:RNA Precursors / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D012326:RNA Splicing; D012333:RNA, Messenger / Q000378:metabolism; D017384:Sequence Deletion; D013329:Structure-Activity Relationship; D014162:Transfection; D014981:Xenopus
D012322:RNA Precursors; D012333:RNA, Messenger; D012319:RNA Polymerase II