3cjk
From Proteopedia
Crystal structure of the adduct HAH1-Cd(II)-MNK1.
Structural highlights
Disease[ATP7A_HUMAN] Defects in ATP7A are the cause of Menkes disease (MNKD) [MIM:309400]; also known as kinky hair disease. MNKD is an X-linked recessive disorder of copper metabolism characterized by generalized copper deficiency. MNKD results in progressive neurodegeneration and connective-tissue disturbances: focal cerebral and cerebellar degeneration, early growth retardation, peculiar hair, hypopigmentation, cutis laxa, vascular complications and death in early childhood. The clinical features result from the dysfunction of several copper-dependent enzymes.[1] [2] [3] [4] [5] [6] [7] [8] [9] Defects in ATP7A are the cause of occipital horn syndrome (OHS) [MIM:304150]; also known as X-linked cutis laxa. OHS is an X-linked recessive disorder of copper metabolism. Common features are unusual facial appearance, skeletal abnormalities, chronic diarrhea and genitourinary defects. The skeletal abnormalities included occipital horns, short, broad clavicles, deformed radii, ulnae and humeri, narrowing of the rib cage, undercalcified long bones with thin cortical walls and coxa valga.[10] [11] Defects in ATP7A are a cause of distal spinal muscular atrophy X-linked type 3 (DSMAX3) [MIM:300489]. DSMAX3 is a neuromuscular disorder. Distal spinal muscular atrophy, also known as distal hereditary motor neuronopathy, represents a heterogeneous group of neuromuscular disorders caused by selective degeneration of motor neurons in the anterior horn of the spinal cord, without sensory deficit in the posterior horn. The overall clinical picture consists of a classical distal muscular atrophy syndrome in the legs without clinical sensory loss. The disease starts with weakness and wasting of distal muscles of the anterior tibial and peroneal compartments of the legs. Later on, weakness and atrophy may expand to the proximal muscles of the lower limbs and/or to the distal upper limbs.[12] Function[ATOX1_HUMAN] Binds and deliver cytosolic copper to the copper ATPase proteins. May be important in cellular antioxidant defense. [ATP7A_HUMAN] May supply copper to copper-requiring proteins within the secretory pathway, when localized in the trans-Golgi network. Under conditions of elevated extracellular copper, it relocalized to the plasma membrane where it functions in the efflux of copper from cells. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe homoeostasis of metal ions in cells is the result of the contribution of several cellular pathways that involve transient, often weak, protein-protein interactions. Metal transfer typically implies the formation of adducts where the metal itself acts as a bridge between proteins, by co-ordinating residues of both interacting partners. In the present study we address the interaction between the human copper(I)-chaperone HAH1 (human ATX1 homologue) and a metal-binding domain in one of its partners, namely the P-type copper-transporting ATPase, ATP7A (ATPase, Cu+ transporting, alpha polypeptide). The adduct was structurally characterized in solution, in the presence of copper(I), and through X-ray crystallography, upon replacing copper(I) with cadmium(II). Further insight was obtained through molecular modelling techniques and site-directed mutagenesis. It was found that the interaction involves a relatively small interface (less than 1000 A(2), 1 A=0.1 nm) with a low fraction of non-polar atoms. These observations provide a possible explanation for the low affinity of the two apoproteins. It appears that electrostatics is important in selecting which domain of the ATPase is able to form detectable amounts of the metal-mediated adduct with HAH1. Copper(I)-mediated protein-protein interactions result from suboptimal interaction surfaces.,Banci L, Bertini I, Calderone V, Della-Malva N, Felli IC, Neri S, Pavelkova A, Rosato A Biochem J. 2009 Jul 29;422(1):37-42. PMID:19453293[13] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Copper-exporting ATPase | Human | Large Structures | Banci, L | Bertini, I | Calderone, V | Della-Malva, N | Felli, I | Pavelkova, A | Rosato, A | Alternative splicing | Atp-binding | Atp7a | Atp7b | Chaperone | Copper | Copper transport | Cytoplasm | Disease mutation | Endoplasmic reticulum | Glycoprotein | Golgi apparatus | Hah1 | Hydrolase | Ion transport | Magnesium | Membrane | Menkes disease | Metal homeostasis | Metal transport-hydrolase complex | Metal-binding | Nucleotide-binding | Phosphoprotein | Polymorphism | Transmembrane | Transport