SelB (Selenocysteine-specific elongation factor) is a transcription factor necessary for the incorporation of selenocysteine into proteins and binds both transfer RNA (tRNA) and mRNA. [1,2,3]. This entry represents a domain that adopts a winged-helix fold, with an alpha/beta structure consisting of three alpha-helices and a twisted three-stranded antiparallel beta-sheet, with an alpha-beta-alpha-alpha-beta-beta connectivity. In SelB, the winged helix domains recognise RNA, allowing the complex to wrap around the small ribosomal subunit [1].

1: Crystal structure of an mRNA-binding fragment of Moorella thermoacetica elongation factor SelB. Selmer M, Su XD; EMBO J. 2002;21:4145-4153. PMID:12145214

2: Conformational switches in winged-helix domains 1 and 2 of bacterial translation elongation factor SelB. Ganichkin O, Wahl MC; Acta Crystallogr D Biol Crystallogr. 2007;63:1075-1081. PMID:17881825

3: Structural basis for mRNA recognition by elongation factor SelB. Yoshizawa S, Rasubala L, Ose T, Kohda D, Fourmy D, Maenaka K; Nat Struct Mol Biol. 2005;12:198-203. PMID:15665870