Fig 5.

Similar levels of MTF-1 mRNA in all tissues except testes. A tissue Northern blot containing a normalized amount of poly A⁺ RNA from various mouse organs was hybridized with a cDNA probe of mouse MTF-1. The autoradiograph reveals the presence of MTF-1 mRNA (black triangle) in all tissues: heart (H), brain (B), spleen (S), lung (Lu), liver (Li), skeletal muscle (M), kidney (K), and testes (T). An upper band (open triangle) that was not seen in a previous Northern blot from liver (not shown) was not further investigated. The extremely high representation of MTF transcripts in testicular tissue was confirmed by quantification of protein by electrophoretic mobility shift (not shown). Similar high testicular transcript levels have been previously reported for other components of the RNA Pol II transcriptional apparatus (Schmidt and Schibler 1995)