5' – RACE analysis of the MsrB1 gene. Agarose gel electrophoresis of size marker and MsrB1 5'-RACE product from purified total RNA using primer RACE -2 (Table 1). The 5' terminal of the sequence of the band from the RACE -2 primer reaction is reported. The upstream sequence from the fragment cloned from the band is in upper case and the arrow indicates the transcription start site (+ 1). The open reading frame codifying for MsrB1 is in lower case and the start codon is in boldface type.