The trace element zinc is required for proper function of a large number of proteins, including various enzymes. However, most zinc-containing proteins are transcription factors capable of binding DNA and are named zinc finger proteins. They are categorized into various families according to zinc-binding motifs. For example, the Cys2His2 family comprises hundreds of zinc finger proteins that are found in eukaryotes ranging from yeast to humans. In contrast, members of the zinc cluster protein family (or binuclear cluster) are exclusively fungal and possess the well-conserved motif CysX2CysX6CysX5-12CysX2CysX6-8Cys. The cysteine residues bind to two zinc atoms, which coordinate folding of the domain involved in DNA binding. The family of zinc cluster proteins is best characterized for the budding yeast, Saccharomyces cerevisiae. The genome of this organism encodes over 50 known (or putative) zinc cluster proteins. The first- and best-studied zinc cluster protein is Gal4p, a transcriptional activator of genes involved in the catabolism of galactose. Zinc cluster proteins are also found in a variety of other fungal organisms, including humans. Like most transcription factors, zinc cluster proteins contain several functional domains apart from the cysteine-rich DNA binding domain, including the regulatory and activation domains. Here you have the crystal structure of SALL4 Zinc-binding protein bound to a 16 bp AT-rich dsDNA (PDB code: 7Y3K)
#molecularart ... #immolecular ... #zinc ... #finger .. #cluster ... #transcription ... #xray
Structure rendered with @proteinimaging and depicted with @corelphotopaint
#molecularart ... #immolecular ... #zinc ... #finger .. #cluster ... #transcription ... #xray
Structure rendered with @proteinimaging and depicted with @corelphotopaint
