Component of the heterotrimeric replication protein A (RPA) and holoenzyme telomerase ribonucleoprotein complexes (PubMed:26472759, PubMed:27895115). As part of the RPA complex, binds and stabilizes single-stranded DNA (ssDNA) intermediates, that form during DNA replication or upon DNA stress (By similarity). It prevents their reannealing and in parallel, recruits and activates different proteins and complexes involved in DNA metabolism (By similarity). Thereby, it plays an essential role both in DNA replication and the cellular response to DNA damage (By similarity). In the cellular response to DNA damage, the RPA complex controls DNA repair and DNA damage checkpoint activation (By similarity). Also part of a subcomplex of the holoenzyme telomerase ribonucleoprotein complex: this subcomplex that contains TEB1, RPA2/TEB2, RPA3/TEB3, but not RPA1, mediates the recruitment of telomerase to telomeric DNA via specific interaction between TEB1 and telomeric ssDNA (PubMed:27895115). In the holoenzyme telomerase ribonucleoprotein complex, RPA2/TEB2 and RPA3/TEB3 act as assembly factors for TEB1 incorporation into telomerase holoenzyme (PubMed:27895115). In the holoenzyme telomerase ribonucleoprotein complex, RPA2/TEB2 does not contribute to ssDNA affinity, while it contributes to ssDNA affinity in the RPA complex (PubMed:27895115). Component of the replication protein A complex (RPA), a heterotrimeric complex composed of RPA1, RPA2/TEB2 and RPA3/TEB3 (PubMed:27895115). 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:26472759, PubMed:29775593). TEB1 and the CST-like subcomplex are tethered to the catalytic core by TAP50/p50 (PubMed:26472759, PubMed:29775593). Belongs to the replication factor A protein 2 family.