The ovalbumin gene: structural sequences in native chicken DNA are not contiguous

Abstract

The sequence organization of the structural ovalbumin gene and flanking sequences in native chicken DNA was studied by restriction mapping and filter hybridization using a nick-translated probe generated from pOV230, a recombinant plasmid that contains a full-length ovalbumin DNA synthesized from ovalbumin mRNA. The structural sequences of the ovalbumin gene in native chicken DNA were found to be noncontiguous because at least two restriction endonucleases that do not cut the structural sequence do cleave the natural gene into multiple fragments by cleaving within nonstructural sequences interspersed between the structural sequences. The observation that all ovalbumin DNA-containing sequences were contained within a single DNA fragment generated by BamHI digestion of total chicken DNA has allowed us to construct an inclusive restriction map of the natural ovalbumin gene which contains at least two "insert regions." These regions may be further subdivided into alternating structural and insert sequences. Both insert regions were located within the peptide-coding regions of the gene and the sizes of these insert regions were estimated to be approximately 1.0 and 1.5 kilobase pairs, respectively.