Mapping 3' termini of mitochondrial 7S RNA/early LSP transcripts in control (L/L) and Tefm knockout (L/L, cre) mouse hearts at the age of 8 weeks. A 3' RACE was performed using linker-ligated RNA and a forward primer corresponding to the first 45 bp from the transcription initiation site at LSP. CSB, conserved sequence block. 