Lien vers Pubmed [PMID] – 29656238
Lien vers HAL – Cliquez ici
Lien DOI – 10.1016/j.sbi.2018.03.019
Curr. Opin. Struct. Biol. 2018 12;53:22-31
Terminal deoxynucleotidyltransferase (TdT) is a member of the polX family which is involved in DNA repair. It has been known for years as an untemplated DNA polymerase used during V(D)J recombination to generate diversity at the CDR3 region of immunoglobulins and T-cell receptors. Recently, however, TdT was crystallized in the presence of a complete DNA synapsis made of two double-stranded DNA (dsDNA), each with a 3′ protruding end, and overlapping with only one micro-homology base-pair, thus giving structural insight for the first time into DNA synthesis across strands. It was subsequently shown that TdT indeed has an in trans template-dependent activity in the presence of an excess of the downstream DNA duplex. A possible biological role of this dual activity is discussed.