Protein coding sequences in newly synthesized nuclear RNA from chicken immature red blood cells.

The contents of globin gene transcripts and other protein coding agene transcript (preferentially expressed in liver) within nuclear RNA from chicken immature red blood cells were analyzed by the method of cDNA hybridization. A comparison of the hybridization values obtained from steady state nuclear RNA and pulse labeled newly synthesized nuclear RNA demonstrated, that (a) there is a vast excess of globin gene transcripts over other individual protein coding transcripts and (b) the ratio of globin gene transcripts to the amount of other protein gene transcripts is nearly the same within both RNA species. We conclude, that in chicken immature red blood cells the globin genes are transcribed either at a much higher rate than other protein coding genes or that most of the transcription products of other genes transcribed at higher rates must be degraded during or very shortly after transcription. Moreover, an accumulation of both types of transcripts was observed, as the contents of these RNA molecules was higher within steady state nuclear RNA than within the newly synthesized RNA.