Analysis of histone H5 and globin mRNAs in chick-embryo development

Transcripts from histone H5 and alpha and beta chicken globin genes were analysed in total RNA extracted from 2-6-day-old chick embryos. Denatured RNA, separated on gels, was transferred to either aminophenylthioether (APT) paper or to nitrocellulose and was detected with 32P-labelled recombinant DNA probes. Good resolution was achieved with methyl mercury hydroxide gels and aminophenylthioether transfer, allowing estimation of H5 and alpha and beta globin mRNA sizes. With glyoxal gels and nitrocellulose transfer, alpha and beta globin mRNAs were not resolved, but an increased sensitivity of detection of at least 10-fold was achieved. Levels of H5 and alpha globin mRNAs increased in parallel over 2-6 days. The appearance of definitive red cells in 6-day embryos was indicated by detection of adult beta globin transcripts at this stage.