CST complex subunit CTC1 (Ctc1)

Part of the CST complex proposed to act as a technical replication factor promoting DNA replication under conditions of replication stress or natural replication barriers such as the telomere duplex. The CST complex binds single-stranded DNA with high affinity in a sequence-independent fashion, while isolated subunits bind DNA with low affinity by themselves.

Initially the CST complex was proposed to protect telomeres from DNA degradation (PubMed:19854130). However, the CST complex was demonstrated to be involved in several facets of telomere replication.