1zim
From Proteopedia
GCN4-LEUCINE ZIPPER CORE MUTANT ASN16GLN IN THE TRIMERIC STATE
Structural highlights
FunctionGCN4_YEAST Is a transcription factor that is responsible for the activation of more than 30 genes required for amino acid or for purine biosynthesis in response to amino acid or purine starvation. Binds and recognize the DNA sequence: 5'-TGA[CG]TCA-3'. Publication Abstract from PubMedA conserved asparagine (Asn 16) buried in the interface of the GCN4 leucine zipper selectively favours the parallel, dimeric, coiled-coil structure. To test if other polar residues confer oligomerization specificity, the structural effects of Gln and Lys substitutions for Asn 16 were characterized. Like the wild-type peptide, the Asn 16Lys mutant formed exclusively dimers. In contrast, Gln 16, despite its chemical similarity to Asn, allowed the peptide to form both dimers and trimers. The Gln 16 side chain was accommodated by qualitatively different interactions in the dimer and trimer crystal structures. These findings demonstrate that the structural selectivity of polar residues results not only from the burial of polar atoms, but also depends on the complementarity of the side-chain stereochemistry with the surrounding structural environment. Buried polar residues and structural specificity in the GCN4 leucine zipper.,Gonzalez L Jr, Woolfson DN, Alber T Nat Struct Biol. 1996 Dec;3(12):1011-8. PMID:8946854[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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