2odu
From Proteopedia
Crystal structure of a fragment of the plakin domain of plectin
Structural highlights
DiseasePLEC_HUMAN Defects in PLEC are the cause of epidermolysis bullosa simplex with pyloric atresia (EBS-PA) [MIM:612138. EBS-PA is an autosomal recessive genodermatosis characterized by severe skin blistering at birth and congenital pyloric atresia. Death usually occurs in infancy. This disorder is allelic to MD-EBS.[1] [2] [3] Defects in PLEC are the cause of epidermolysis bullosa simplex with muscular dystrophy (MD-EBS) [MIM:226670. MD-EBS is an autosomal recessive disorder characterized by epidermal blister formation at the level of the hemidesmosome and associated with late-onset muscular dystrophy. Defects in PLEC are the cause of epidermolysis bullosa simplex Ogna type (O-EBS) [MIM:131950; also called epidermolysis bullosa simplex 1. O-EBS is a form of intraepidermal epidermolysis bullosa characterized by generalized skin bruising, skin fragility with non-scarring blistering and small hemorrhagic blisters on hands. At the ultrastructural level, it is differentiated from classical cases of K-EBS, WC-EBS and DM-EBS, by the occurrence of blisters originating in basal cells above hemidesmosomes, and abnormal hemidesmosome intracellular attachment plates. Defects in PLEC are the cause of limb-girdle muscular dystrophy type 2Q (LGMD2Q) [MIM:613723. An autosomal recessive degenerative myopathy characterized by early childhood onset of proximal muscle weakness. Note=A 9 bp deletion containing the initiation codon in exon 1f of PLEC have been found in limb-girdle muscular dystrophy patients. The mutation results in deficient expression of isoform 9 and disorganization of the myofibers, without any effect on the skin.[4] [5] FunctionPLEC_HUMAN Interlinks intermediate filaments with microtubules and microfilaments and anchors intermediate filaments to desmosomes or hemidesmosomes. Could also bind muscle proteins such as actin to membrane complexes in muscle. May be involved not only in the filaments network, but also in the regulation of their dynamics. Structural component of muscle. Isoform 9 plays a major role in the maintenance of myofibers integrity.[6] [7] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedPlectin is a large and versatile cytoskeletal linker and member of the plakin protein family. Plakins share a conserved region called the plakin domain located near their N terminus. We have determined the crystal structure of an N-terminal fragment of the plakin domain of plectin to 2.05 A resolution. This region is adjacent to the actin-binding domain and is required for efficient binding to the integrin alpha6beta4 in hemidesmosomes. The structure is formed by two spectrin repeats connected by an alpha-helix that spans these two repeats. While the first repeat is very similar to other known structures, the second repeat is structurally different with a hydrophobic core, narrower than that in canonical spectrin repeats. Sequence analysis of the plakin domain revealed the presence of up to nine consecutive spectrin repeats organized in an array of tandem modules, and a Src-homology 3 domain inserted in the central spectrin repeat. The structure of the plakin domain is reminiscent of the modular organization of members of the spectrin family. The architecture of the plakin domain suggests that it forms an elongated and flexible structure, and provides a novel molecular explanation for the contribution of plectin and other plakins to the elasticity and stability of tissues subjected to mechanical stress, such as the skin and striated muscle. The structure of a tandem pair of spectrin repeats of plectin reveals a modular organization of the plakin domain.,Sonnenberg A, Rojas AM, de Pereda JM J Mol Biol. 2007 May 18;368(5):1379-91. Epub 2007 Mar 7. PMID:17397861[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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