DNA repair enzyme that can remove a variety of covalent adducts from DNA through hydrolysis of a 5'-phosphodiester bond, giving rise to DNA with a free 5' phosphate. Catalyzes the hydrolysis of dead- end complexes between DNA and the topoisomerase 2 (TOP2) active site tyrosine residue. The 5'-tyrosyl DNA phosphodiesterase activity can enable the repair of TOP2-induced DNA double-strand breaks/DSBs without the need for nuclease activity, creating a 'clean' DSB with 5'- phosphate termini that are ready for ligation (PubMed:27060144, PubMed:27099339). Thereby, protects the transcription of many genes involved in neurological development and maintenance from the abortive activity of TOP2. Hydrolyzes 5'-phosphoglycolates on protruding 5' ends on DSBs due to DNA damage by radiation and free radicals. Has preference for single-stranded DNA or duplex DNA with a 4 base pair overhang as substrate. Acts as a regulator of ribosome biogenesis following stress. Also has 3'-tyrosyl DNA phosphodiesterase activity, but less efficiently and much slower than TDP1. Constitutes the major if not only 5'-tyrosyl-DNA phosphodiesterase in cells. Also acts as an adapter by participating in the specific activation of MAP3K7/TAK1 in response to TGF-beta: associates with components of the TGF-beta receptor-TRAF6-TAK1 signaling module and promotes their ubiquitination dependent complex formation. Involved in non-canonical TGF-beta induced signaling routes. May also act as a negative regulator of ETS1 and may inhibit NF-kappa-B activation. {ECO:0000269|PubMed:19794497, ECO:0000269|PubMed:21030584, ECO:0000269|PubMed:21921940, ECO:0000269|PubMed:21980489, ECO:0000269|PubMed:22405347, ECO:0000269|PubMed:22822062, ECO:0000269|PubMed:24658003, ECO:0000269|PubMed:27060144, ECO:0000269|PubMed:27099339}. (Microbial infection) Used by picornaviruses to remove the small polypeptide, VPg (virus Protein genome-linked, the primer for viral RNA synthesis), from the genomic RNA of the virus. Acts as a 5'- tyrosyl RNA phosphodiesterase and cleaves the covalent VPg-Tyr-RNA bond. This cleavage would play a role in viral replication and occur in viral replication vesicles, but would not act on viral mRNA. . This is the function of TDP2 (tyrosyl-DNA phosphodiesterase 2, Ensembl gene identifier ENSG00000111802).