We have determined the complete nucleotide sequence of βh2, a pseudogene in the mouse β-globin gene complex. The structure of βh2 is analogous to that of a normal β-globin gene, and its nucleotide sequence shares 72% homology with the coding regions of a reference mouse adult β-globin gene. A frame shift occurs in the first coding region for which a compensatory splicing scheme can be devised. The reading frame is not otherwise disrupted. All of the recognized transcription, translation, and splicing signals in βh2 are intact, with the exception of the 'CCAAT box', which has been altered to GTAAC. We compared the predicted amino acid sequence of βh2 with other β-globin sequences. Evidence for a period of divergence without selection in the history of βh2 was found in a set of codons that are usually highly conserved in productive β-globin genes. An evolutionary tree constructed from nucleotide sequence suggests that βh2 originated from the adult genes at least 60 million years ago. After some period as a productive gene, βh2 was inactivated and has subsequently diverged without selection. Hybridization experiments demonstrated that βh2 and the surrounding region occur without major alteration in other rodent species. The sequence (AGCCA-4n-GTGT) occurs 5' of the CCAAT box in βh2 and in many productive globin genes.
|Original language||English (US)|
|Number of pages||8|
|Journal||Journal of Biological Chemistry|
|State||Published - 1984|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology