Multiple positive and negative 5' regulatory elements control the cell-type-specific expression of the embryonic skeletal myosin heavy-chain gene.

摘要: To identify the DNA sequences that regulate expression of sarcomeric myosin heavy-chain (MHC) genes in muscle cells, a series deletion constructs rat embryonic MHC gene was assayed for transient after introduction into myogenic and nonmyogenic cells. The 1.4 kilobases 5'-flanking were found to be sufficient direct tissue-specific manner (i.e., differentiated cells but not undifferentiated nonmuscle cells). Three main distinct regulatory domains have been identified: (i) upstream from positions -1413 -174, which determine level are constituted three positive elements two negative ones; (ii) muscle-specific element -173 -142, restricts cells; (iii) promoter region, downstream position -102, directs transcription initiation. Introduction simian virus 40 enhancer where subportions or all deleted (up -173) strongly increases such truncated without changing their specificity. These sequences, can substituted by enhancer, function an orientation-, position-, promoter-dependent fashion. is also specific does support efficient gene. itself specific. results underline importance concerted action multiple likely represent targets DNA-binding-regulatory proteins.