RNA Polymerase II Phosphorylated on CTD Serine 5 Interacts with the Spliceosome during Co-transcriptional Splicing.
Mol Cell
; 72(2): 369-379.e4, 2018 10 18.
Article
en En
| MEDLINE
| ID: mdl-30340024
ABSTRACT
The highly intronic nature of protein coding genes in mammals necessitates a co-transcriptional splicing mechanism as revealed by mNET-seq analysis. Immunoprecipitation of MNase-digested chromatin with antibodies against RNA polymerase II (Pol II) shows that active spliceosomes (both snRNA and proteins) are complexed to Pol II S5P CTD during elongation and co-transcriptional splicing. Notably, elongating Pol II-spliceosome complexes form strong interactions with nascent transcripts, resulting in footprints of approximately 60 nucleotides. Also, splicing intermediates formed by cleavage at the 5' splice site are associated with nearly all spliced exons. These spliceosome-bound intermediates are frequently ligated to upstream exons, implying a sequential, constitutive, and U12-dependent splicing process. Finally, lack of detectable spliced products connected to the Pol II active site in human HeLa or murine lymphoid cells suggests that splicing does not occur immediately following 3' splice site synthesis. Our results imply that most mammalian splicing requires exon definition for completion.
Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Fosforilación
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Serina
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Transcripción Genética
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ARN Polimerasa II
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Empalme del ARN
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Empalmosomas
Límite:
Animals
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Humans
Idioma:
En
Revista:
Mol Cell
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
2018
Tipo del documento:
Article
País de afiliación:
Reino Unido