The basic repeat unit of a Chironomus Balbiani ring gene.
A clone derived from the Balbiani ring b (BRb) gene of Chironomus thummi has been used to study the internal organization of that gene. Much of the gene consists of approximately 80 copies of a ca. 300 bp repeat unit, which are tandemly organized. The BRb clone contains a major part of that unit (242 bp). Sequence analysis shows that approximately 60% of the unit corresponds to short, tandemly organized subsequences, which encode peptides 8 to 11 residues long. In turn, each subsequence consists of even shorter internal repeats, corresponding to a tripeptide (consensus Proline. Serine. Lysine.). The remainder of the ca. 300 bp unit probably does not have obvious repetitive substructure.
D000818:Animals; D001482:Base Composition; D001483:Base Sequence; D002683:Chironomidae / Q000235:genetics*; D003001:Cloning, Molecular; D004175:Diptera / Q000235:genetics*; D005796:Genes; D008970:Molecular Weight; D009693:Nucleic Acid Hybridization; D012091:Repetitive Sequences, Nucleic Acid; D014158:Transcription, Genetic