Tissue distribution of the murine PR130/B"α1, PR72/B"α2, PR59/B"δ1/2 transcripts. A first choice Mouse Blot I containing poly(A+) RNAs from ten different murine tissues (Clontech) was hybridised with isoform-specific RNA probes. For quantification we used the ImageQuant program from Molecular Dynamics. Percentages of expression are relative to the most intense band on each blot, which was given a value of 100%. Therefore only transcripts present on the same blot can be compared. A β-actin control hybridisation is shown at the bottom.