cDNA, protein, and genomic organization of C. elegans sbp2 gene coding for a SECIS-binding protein. (A) Amplification of the full-length sbp2 mRNA with SL1 as forward primer and a reverse specific primer. A 493-bp product corresponding to the full-length cDNA was obtained (lane 1), 100-bp gene ruler (lane 2). (B) The conceptual translation of the amplified mRNA shows that the reading frame remains open upstream of the first in-frame ATG codon (dotted frame) and that there is an ATT codon at the beginning of the cDNA (bold frame) in a favorable Caenorhabditis Kozak context. (C) The gene model proposed by WormBase (black and white rectangles correspond to coding and noncoding exons, respectively), codes for an 85-amino-acid-long protein and has a long 5′ UTR and a truncated RBD (gray). The first in-frame ATG codon is indicated in gray. (D) The gene model put forward in the present work codes for a 153-amino-acid-long protein with a short 5′ UTR and a complete RBD. The ATT codon that serves for translation initiation is indicated in gray.