1d66 is a 4 chain structure with sequence from Atcc 18824. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
[GAL4_YEAST] This protein is a positive regulator for the gene expression of the galactose-induced genes such as GAL1, GAL2, GAL7, GAL10, and MEL1 which code for the enzymes used to convert galactose to glucose. It recognizes a 17 base pair sequence in (5'-CGGRNNRCYNYNCNCCG-3') the upstream activating sequence (UAS-G) of these genes. This sequence is correctly shown on the structure as (5'-CGGAGGACTGCCCTCCG-3'). The DNA-Protein Interaction with all of the base pairs within 5 angstroms of the protein highlighted illustrates that the protein interacts with both strands of the UAS.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
A specific DNA complex of the 65-residue, N-terminal fragment of the yeast transcriptional activator, GAL4, has been analysed at 2.7 A resolution by X-ray crystallography. The protein binds as a dimer to a symmetrical 17-base-pair sequence. There is a compact metal binding domain (residues 8-40), an extended linker (41-49), and an alpha-helical dimerization element (50-64). A small, Zn(2+)-containing domain recognizes a conserved CCG triplet at each end of the site through direct contacts with the major groove. The metal binding domain contains cysteine residues that coordinate to the metal as shown as cadmium. A short coiled-coil dimerization element imposes 2-fold symmetry. A segment of extended polypeptide chain links the metal-binding module to the dimerization element and specifies the length of the site. The relatively open structure of the complex would allow another protein to bind coordinately with GAL4.
DNA recognition by GAL4: structure of a protein-DNA complex.,Marmorstein R, Carey M, Ptashne M, Harrison SC Nature. 1992 Apr 2;356(6368):408-14. PMID:1557122[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑Marmorstein R, Carey M, Ptashne M, Harrison SC. DNA recognition by GAL4: structure of a protein-DNA complex. Nature. 1992 Apr 2;356(6368):408-14. PMID:1557122 doi:https://dx.doi.org/10.1038/356408a0
STRUCTURE OF Cas9 IN STAPHYLOCOCCUS AUREUS IN COMPLEX WITH gRNA
Cas9 Overview
CRISPR is a bacterial immune response to bacteriophages to prevent subsequent infections and is a form of acquired immunity. Within the CRISPR system, Cas9 is a protein responsible for cutting the viral DNA rendering it inert. Cas9 structure in Staphylococcus aureus (SaCas9) utilizes a single stranded guide RNA (sgRNA) to bind the target DNA that will be cut. The target DNA must also have a PAM sequence to bind to Cas9 to be cut. Cas9 has four main mechanisms that are important for successful cleavage including recognition of the sgRNA-target heteroduplex, recognition of the PAM sequence, recognition of the sgRNA scaffold, and endonuclease activity by HNH and RuvC.
