https://www.auburn.edu/academic/classes/biol/6190/refs/L04/1-s2.0-S0092867402009716-main.pdf

Integrins: Bidirectional, Allosteric Signaling Machines

https://www.cell.com/cell/pdf/S0092-8674(00)80434-1.pdf

Cytochrome c and dATP-Dependent Formation of Apaf-1/Caspase-9 Complex Initiates an Apoptotic Protease Cascade

The SREBP Pathway: Regulation of Cholesterol Metabolism by Proteolysis of a Membrane-Bound Transcription Factor

https://www.univie.ac.at/ibmz/student/results/apoptosis1.pdf

Apaf-1, a Human Protein Homologous to C. elegans CED-4, Participates in Cytochrome c–Dependent Activation of Caspase-3

G protein-coupled receptors (GPCRs) are responsible for the majority of cellular responses to hormones and neurotransmitters as well as the senses of sight, olfaction and taste. The paradigm of GPCR signalling is the activation of a heterotrimeric GTP binding protein (G protein) by an agonist-occupied receptor. The b2 adrenergic receptor (b2AR) activation of Gs, the stimulatory G protein for adenylyl cyclase, has long been a model system for GPCR signalling. Here we present the crystal structure of the active state ternary complex composed of agonist-occupied monomericb2AR and nucleotide-free Gs heterotrimer. The principal interactions between the b2AR and Gs involve the amino- and carboxy-terminal a-helices of Gs, with conformational changes propagating to the nucleotide-binding pocket. The

/pdf/crystal-structure-of-the-b2-adrenergic-receptor-gs-protein-c8p8r5g8uj.pdf

Crystal structure of the β2 adrenergic receptor-Gs protein complex.

The structure of the G protein heterotrimer Giα1β1γ2

A fundamental goal in cellular signaling is to understand allosteric communication, the process by which signals originating at one site in a protein propagate reliably to affect distant functional sites. The general principles of protein structure that underlie this process remain unknown. Here, we describe a sequence-based statistical method for quantitatively mapping the global network of amino acid interactions in a protein. Application of this method for three structurally and functionally distinct protein families (G protein–coupled receptors, the chymotrypsin class of serine proteases and hemoglobins) reveals a surprisingly simple architecture for amino acid interactions in each protein family: a small subset of residues forms physically connected networks that link distant functional sites in the tertiary structure. Although small in number, residues comprising the network show excellent correlation with the large body of mechanistic data available for each family. The data suggest that evolutionarily conserved sparse networks of amino acid interactions represent structural motifs for allosteric communication in proteins.

/pdf/evolutionarily-conserved-networks-of-residues-mediate-5cqdmrnq5j.pdf

Evolutionarily conserved networks of residues mediate allosteric communication in proteins

Green fluorescent protein (GFP) has rapidly become a standard tool for investigating a variety of cellular activities, and has served as a model system for understanding spectral tuning in chromophoric proteins. Distant homologs of GFP in reef coral and anemone display two new properties of the fluorescent protein family: dramatically red-shifted spectra, and oligomerization to form tetramers. We now report the 1.9 A crystal structure of DsRed, a red fluorescent protein from Discosoma coral. DsRed monomers show similar topology to GFP, but additional chemical modification to the chromophore extends the conjugated pi-system and likely accounts for the red-shifted spectra. Oligomerization of DsRed occurs at two chemically distinct protein interfaces to assemble the tetramer. The DsRed structure reveals the chemical basis for the functional properties of red fluorescent proteins and provides the basis for rational engineering of this subfamily of GFP homologs.

The structural basis for red fluorescence in the tetrameric GFP homolog DsRed.

https://www.cell.com/structure/pdf/S0969-2126(98)00117-8.pdf

Mark A. Wall

Papers

The structure of the G protein heterotrimer Giα1β1γ2

Evolutionarily conserved networks of residues mediate allosteric communication in proteins

The structural basis for red fluorescence in the tetrameric GFP homolog DsRed.

Structural basis of activity and subunit recognition in G protein heterotrimers

Dynamic Scaffolding in a G Protein-Coupled Signaling System