Organization of the bovine α2-fucosyltransferase gene cluster suggests that the Sec1 gene might have been shaped through a nonautonomous l1-retrotransposition event within the same locus

Abstract

By referring to the split coding sequence of the highly conserved α6-fucosyltransferase gene family (assumed to be representative of the common α2 and α6 fucosyltransferase gene ancestor), we have hypothesized that the monoexonic coding sequences of the present α2-fucosyltransferase genes have been shaped in mammals by several events of retrotransposition and/or duplication. In order to test our hypothesis, we determined the structure of the three bovine α2-fucosyltransferase genes, bfut2, and sec1) and analyzed their characteristics compared with their human counterparts (FUT1, FUT2, and Sec1). We show that in mammals, a complex nonautonomous L1retrotransposition event occurred within the locus of the α2-fucosyltransferase ancestor gene itself. A consequence of this event was the processing in Catarrhini of a Sec1 pseudogene via several point mutations.