This gene encodes an essential component of the telomerase holoenzyme complex, a ribonucleoprotein complex required for telomere synthesis. This protein is enriched in Cajal bodies, nuclear sites of RNP processing that are important for telomerase function. It interacts with dyskerin, TERT and TERC, other components of active telomerase, and with small Cajal body RNAs (scaRNAs), which are involved in modifying splicing RNAs. This mRNA also functions as a p53 antisense transcript, that regulates endogenous p53 mRNA levels and further induction of p53 protein by targeting the 5' untranslated region of p53 mRNA. Alternatively spliced transcript variants which differ only in the 5' UTR have been found for this gene. [provided by RefSeq, Mar 2011].