The nucleotide sequence of an 8.2-kb DNA fragment from the 5' proximal part of the chicken myb proto-oncogene spanning 1761 nucleotides upstream and 6436 nucleotides downstream from a presumed c-myb initiation codon was determined. A 3.3-kb G + C-rich region found in this sequence had also other features characterizing CpG islands, i.e. no CpG underrepresentation and lack of CpG methylation. In haematopoietic tissues c-myb mRNA synthesis starts in two major regions of the CpG island, namely 98 to 108 and 143 to 145 nucleotides upstream from the c-myb initiation codon. These two regions are in or close to the 124-bp evolutionarily conserved element located in the middle part of the CpG island. No alternative splicing of the 5' end of c-myb mRNA suggested earlier (1,2) was observed. The c-myb promoter contains neither TATA nor CAAT box-like structures at the usual positions. Instead, numerous potential Sp1 factor binding sites were found both upstream and downstream from the transcription initiation sites. Moreover, consensus v-myb protein DNA-binding sites were revealed in the promoter region and in sequences downstream from it.

• MeSH
• Dinucleoside Phosphates analysis   MeSH
• Single-Strand Specific DNA and RNA Endonucleases MeSH
• Endonucleases MeSH
• Erythrocytes analysis   MeSH
• Transcription, Genetic * MeSH
• Cloning, Molecular MeSH
• Chickens MeSH
• Molecular Sequence Data MeSH
• Mice MeSH
• Organ Specificity MeSH
• Promoter Regions, Genetic MeSH
• Proto-Oncogene Proteins c-myb MeSH
• Proto-Oncogene Proteins genetics   MeSH
• Proto-Oncogenes * MeSH
• Restriction Mapping MeSH
• RNA Caps genetics   MeSH
• Base Sequence MeSH
• Sequence Homology, Nucleic Acid MeSH
• Thymus Gland analysis   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH
• Names of Substances
• cytidylyl-3'-5'-guanosine MeSH Browser
• Dinucleoside Phosphates MeSH
• Single-Strand Specific DNA and RNA Endonucleases MeSH
• Endonucleases MeSH
• Proto-Oncogene Proteins c-myb MeSH
• Proto-Oncogene Proteins MeSH
• RNA Caps MeSH