ISSN:
0192-253X
Schlagwort(e):
Heat shock promoters
;
HSP70-CAT
;
microinjection
;
linker-scanner mutations
;
Life and Medical Sciences
;
Genetics
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Biologie
Notizen:
Microinjected human HSP70 promoter-chloramphenicol acetyl transferase (CAT) chimeric genes are constitutively expressed immediately after the midblastula transition of Xenopus embryogenesis. Analysis of a series of 5′-deletion mutants in the HSP70 promoter revealed that sequences within 74 bases of the transcriptional start site were sufficient for strong basal activity. We investigated the role of specific sequences in the basal promoter by injecting HSP70-CAT vectors containing linker-scanner mutations in the basal elements (CCAAT, purine-rich element, GC-element, ATF/AP1, and 1ATA). Our data reveal that deletion of any of these cis-acting elements in the basal promoter prevents expression after the midblastula stage of development. Furthermore, we have identified specific binding activities in embryonic nuclear extracts that complex with basal promoter elements (CCAAT, ATF, and GC) of the heterologous HSP70 promoter. These trans-acting factors are detectable in nuclear extracts of early blastula embryos, and their respective binding activity increases dramatically after the midblastula transition. The expression of the human HSP70 gene after the midblastula transition of Xenopus embryogenesis requires an array of cisacting elements, which interact with specific Xenopus transcription factors.
Zusätzliches Material:
9 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/dvg.1020110111
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