Schematic diagram illustrating the exon structure of alternatively spliced FOXP1 isoforms. Blue shaded exons are 5′ noncoding; white is only potentially noncoding as the sequence lacks upstream stop codons. Green exons contain the translational start site (potential for light green shading), yellow exons are coding, while red exons contain the translational stop codon. The positions of key functional motifs in the FOXP1 protein are illustrated above isoform 1.