Tissue expression of TgC mRNA.

TgC and endogenous CSF-1 mRNAs in 10 μg aliquots of total RNA were quantitated by RPA using the exon 9/hGH and exon 10 cDNA probes illustrated in Figure 1A,B. (A) Messenger RNA products protected by the exon 9/hGH probe, which correspond to the exon 9 UTR-containing CSF-1 mRNA (exon 9) and the hGH poly(A) UTR-containing TgC mRNA (Transgene), are indicated. TgC mRNA was detected in each of the tissues examined, apparently at low levels compared with the levels of endogenous CSF-1 mRNA. All samples were electrophoresed in the same gel and the data captured by phosphoimager; intensity of bands in the lower portion of the figure has been reduced to improve resolution. (B) RPA of RNA samples from selected tissues of mice of the indicated genotype, using the exon 9/hGH and exon 10 cDNA probes. Bands representing the exon 9– and exon 10–containing transcripts are indicated. The exon 9 probe generally detects 2 CSF-1–specific bands. Comparison of the 3 panels indicates that exon 9–containing CSF-1 mRNA is decreased inCsf1^op/Csf1^op tissues relative to +/+ tissues and restored to normal inCsf1^op/Csf1^optissues by expression of TgC.