Figure 6.

Ptbp2 inhibits developmentally regulated adult-enriched alternative exons. (A) Distribution of Ptbp2 binding in a region of the c-src gene containing the alternative N1 and N2 exons. Also shown is a BLAT search result following Sanger sequencing of the N1⁺N2⁺ isoform purified from acrylamide gels shown in B. (B) RT–PCR analysis of c-src splicing in both Ptbp2-null strains (and wild-type littermates, left and center panels) and in neonatal (P1) and adult (P50) wild-type brains (right panel). Control lanes correspond to cDNA mixtures amplified at different cycle numbers (see the Materials and Methods). (C) Quantification of c-src RT–PCR products from B. (D–F) Analysis of Ptbp2-regulated exons in Cep350, Rab28, and Mta3 in wild-type and Ptbp2-null E18.5 brains (left) and wild-type neonatal and adult brains (right). (G) Western blot analysis of Ptbp2 and Hsp90 in wild-type brains at the indicated embryonic and postnatal days.