InterPro domain: IPR045153

This entry includes Est1/Esl1/Esl2/Ebs1 from budding yeasts and Est1A/SMG6/SMG7 from humans. Est1 is a TLC1 RNA-associated factor involved in telomere length regulation [ 1 , 2 ]. Ebs1, an Est1 paralogue and human Smg7 orthologue, is involved in translation inhibition and nonsense-mediated decay [ 3 ]. Esl1 and Esl2 are not involved in nonsense-mediated mRNA decay or telomere maintenance pathways, instead, they regulate adaptive gene expression responses of environmental sensing pathways [ 4 ].

1. The Est1 subunit of yeast telomerase binds the Tlc1 telomerase RNA. Mol Cell Biol 20, 1947-55
2. Est1p as a cell cycle-regulated activator of telomere-bound telomerase. Science 297, 1023-6
3. Saccharomyces cerevisiae Ebs1p is a putative ortholog of human Smg7 and promotes nonsense-mediated mRNA decay. Nucleic Acids Res 35, 7688-97
4. Yeast hEST1A/B (SMG5/6)-like proteins contribute to environment-sensing adaptive gene expression responses. G3 (Bethesda) 3, 1649-59