This gene encodes a protein which is part of the telomerase ribonucleoprotein complex and binds single-stranded DNA found at the telomeres, but the product of this gene also participates in the nonsense-mediated mRNA decay (NMD) pathway. The encoded protein contains two binding sites for components of the exon junction complex (EJC)\; interaction between the encoded protein and the EJC is necessary for NMD activity. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2012].