Tissue-specific expression of PDE7B. (A) Northern blot analysis of PDE7B expression. Each lane contained 2 μg of mouse poly(A) RNA. The blot was hybridized with a 310-bp fragment of PDE7B cDNA (nucleotides 131–441). RNA length is indicated by the numbers at the left (kb). A single band, 5.6 kb in size, is present in heart, brain, liver, and skeletal muscle. (B) Dot blot analysis of PDE7B expression. Mouse poly(A) RNA dot blots were hybridized as described in A. PDE7B message is detected in pancreas, brain, heart, skeletal muscle, eye, thyroid, ovary, testis, submaxillary gland, epididymus, and liver. Please note the strongest signal is in pancreas.