The GAL4 Protein The GAL4 is a yeast activator that control a set of gene responsible for metabolism of galactose. Targeting the enhancer:upstream activating sequnces(上游激活序列，UASGS) a member of the zinc-containing family It does not have a zinc finger 12-11
12-11 The GAL4 Protein ✓ The GAL4 is a yeast activator that control a set of gene responsible for metabolism of galactose. ✓ Targeting the enhancer: upstream activating sequnces (上游激活序列, UASGS ) ✓ a member of the zinc-containing family ✓ It does not have a zinc finger
The GAL4 Protein GAL4 monomer contains a DNA- binding motif with: 6 cysteines that coordinate 2 zinc ions in a bimetal thiolate cluster (双金属巯基簇) Short a-helix that protrudes into the DNA major groove is the recognition module Dimerization motif with an a-helix that forms a parallel coiled coil (螺旋圈)as it interacts with the a helix on another GAL4 monomer
12-12 The GAL4 Protein GAL4 monomer contains a DNAbinding motif with: – 6 cysteines that coordinate 2 zinc ions in a bimetal thiolate cluster (双金属巯基簇) – Short a-helix that protrudes into the DNA major groove is the recognition module – Dimerization motif with an a-helix that forms a parallel coiled coil (螺旋圈) as it interacts with the ahelix on another GAL4 monomer
The Nuclear Receptors(核受体) A third class of zinc module is the nuclear receptor This type of protein interacts with a variety of endocrine-signaling(内分泌信号)molecules Protein plus endocrine molecule forms a complex that functions as an activator by binding to hormone response elements and stimulating transcription of associated genes 12-13
12-13 The Nuclear Receptors (核受体) ✓ A third class of zinc module is the nuclear receptor ✓ This type of protein interacts with a variety of endocrine-signaling (内分泌信号) molecules ✓ Protein plus endocrine molecule forms a complex that functions as an activator by binding to hormone response elements and stimulating transcription of associated genes