Single-stranded DNA (ssDNA)-binding protein that mediates the recruitment of telomerase to telomeric DNA (PubMed:19941821, PubMed:20363756, PubMed:25225329, PubMed:22143754). Telomerase is an essential ribonucleoprotein (RNP) enzyme that copies new telomeric repeats onto chromosome ends by repetitively synthesizing the short telomere-repeat sequence 5'-TTGGGG-3' using an RNA template component TER (PubMed:19941821). Acts as part of a replication protein A (RPA)-related subcomplex of the holoenzyme telomerase ribonucleoprotein complex: TEB1 specifically recognizes and binds telomeric ssDNA, thereby mediating the recruitment of the holoenzyme telomerase RNP complex to telomeres (PubMed:19941821, PubMed:25225329, PubMed:27895115). TEB1 is related to RPA1 subunit of the RPA complex but is specific to telomeric DNA, which is not the case of RPA1 (PubMed:25225329). Component of the telomerase holoenzyme complex, composed of the catalytic core (the catalytic subunit TERT, the telomerase RNA template component TER and TAP65/p65), which is associated with two heterotrimeric subcomplexes: (i) the replication protein A (RPA)-related subcomplex, composed of TEB1, RPA2/TEB2 and RPA3/TEB3 and (ii) the CST-like subcomplex, composed of TAP75/p75, TAP45/p45 and TAP19/p19 (PubMed:19941821, PubMed:27895115, PubMed:23552895, PubMed:26472759, PubMed:29775593). TEB1 and the CST-like subcomplex are tethered to the catalytic core by TAP50/p50 (PubMed:19941821, PubMed:23552895, PubMed:26472759, PubMed:29775593). Critically short telomeres. Belongs to the replication factor A protein 1 family.