Fig. 5. RNase protection assay from tissue-derived mRNA. RNase protection assays were performed with 0.5 µg of polyA⁺ RNA derived from different tissues as illustrated. The probe, `RPA-2', was radioactively labeled and incubated with or without tissue mRNA as in Fig. 4A. Relative values of LTBP-4 mRNAs (see text for details) compared with LTBP-4 levels in the heart (set as 100%). Phosphoimager quantification of two separate experiments is presented with error bars. (Inset) RNase protection assay of heart and lung mRNAs. The protected fragments corresponding to LTBP-4 containing the 3^rd 8-Cys repeat, LTBP-48-Cys^3rd as well as LTBP-4EGF-13 are indicated on the right. The mobilities of the molecular weight markers (nt) are shown on the left of the inset.