High impact information on MTF-1

• The metal response element-binding transcription factor-1 (MTF-1) recruits TFIID, which then binds promoter DNA, setting up a "checkpoint complex" for the initiation of transcription that is subsequently activated upon recruitment of the MED complex [1].
• 'Metal-responsive transcription factor-1' (MTF-1), a zinc finger protein, is conserved from mammals to insects [2].
• These findings expand the roles of MTF-1 in the control of heavy metal homeostasis [2].
• The knockout of MTF-1 in the mouse has an embryonic lethal phenotype accompanied by liver degeneration [2].
• Strikingly, metallothionein mutants show an increased, MTF-1-dependent induction of metallothionein promoters in response to copper, cadmium, silver, zinc, and mercury [3].

Biological context of MTF-1

• Heavy metal induction of both Drosophila MTs is abolished by double-stranded RNA interference: small amounts of cotransfected double-stranded RNA of dMTF-1 but not of unrelated control RNA inhibit the response to both the endogenous dMTF-1 and transfected dMTF-1 [4].

Other interactions of MTF-1

• We conclude that free metal, but not metallothionein-bound metal, triggers the activation of MTF-1 and that metallothioneins regulate their own expression by a negative feedback loop [3].

References