InterPro domain: IPR024481

The yeast helicase Sen1 is an ATP-dependent 5'->3' DNA/RNA helicase required for the expression and maturation of diverse classes of non-protein-coding RNAs like precursor tRNAs, rRNAs and small nuclear (snRNA) and nucleolar (snoRNA) RNAs [ 1 , 2 ] and it also has an ATPase-dependent ability of promoting transcription termination in vitro [ 3 ]. Sen1 has a key role at replication forks during DNA replication to promote fork progression and chromosome stability [ 4 ]. Sen1 belongs to the superfamily 1B UPF1-like family of helicases with a common domain organisation: a N-terminal domain and a C-terminal domain which contains the SF1B RNA helicase with two RecA domains (RecA1 and RecA2) and the classical helicase motifs involved in nucleic acid binding and ATP hydrolysis. It also contains two SF1B‐specific subdomains (1B and 1C) that modulate RNA binding. This entry represents the large N-terminal domain, a characteristic feature of this protein, which is important for Sen1 function in vivo. It is sufficient and necessary for replisome association as it contains the interaction sites for replisome components [ 5 , 5 , 5 , 5 ].

1. Repression of gene expression by an exogenous sequence element acting in concert with a heterogeneous nuclear ribonucleoprotein-like protein, Nrd1, and the putative helicase Sen1. Mol. Cell. Biol. 16, 6993-7003
2. Multiple protein/protein and protein/RNA interactions suggest roles for yeast DNA/RNA helicase Sen1p in transcription, transcription-coupled DNA repair and RNA processing. Nucleic Acids Res. 32, 2441-52
3. Sen1 has unique structural features grafted on the architecture of the Upf1-like helicase family. EMBO J 36, 1590-1604
4. Sen1 Is Recruited to Replication Forks via Ctf4 and Mrc1 and Promotes Genome Stability. Cell Rep 30, 2094-2105.e9
5. SEN1, a positive effector of tRNA-splicing endonuclease in Saccharomyces cerevisiae. Mol. Cell. Biol. 12, 2154-64