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III Domain (iii + domain)

Distribution by Scientific Domains

Chemistry	83%

Selected Abstracts

Syndromic craniosynostosis: from history to hydrogen bonds

ORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 2 2007
ML Cunningham
Structured Abstract Authors,,, Cunningham ML, Seto ML, Ratisoontorn C, Heike CL, Hing AV The syndromic craniosynostoses, usually involving multiple sutures, are hereditary forms of craniosynostosis associated with extracranial phenotypes such as limb, cardiac, CNS and tracheal malformations. The genetic etiology of syndromic craniosynostosis in humans is only partially understood. Syndromic synostosis has been found to be associated with mutations of the fibroblast growth factor receptor family (FGFR1, -R2, -R3), TWIST1, MSX2, and EFNB1. Apert, Pfeiffer, Crouzon, and Jackson-Weiss syndromes are due to gain-of-function mutations of FGFR2 in either the Ig II,III linker region (Apert) or Ig III domain. Loss of function mutations of TWIST1 and gain-of-function mutations of MSX2 lead to Saethre,Chotzen and Boston-type syndromes, respectively. The mutations in Pfeiffer (FGFR1), Muenke (FGFR3), and Apert syndrome (FGFR2) are caused by the same amino acid substitution in a highly conserved region of the Ig II,III linker region of these proteins, which suggests that these receptor tyrosine kinases have an overlapping function in suture biology. In this review we will discuss the historical descriptions, current phenotypes and molecular causes of the more common forms of syndromic craniosynostosis. [source]

An experimental study of GFP-based FRET, with application to intrinsically unstructured proteins

PROTEIN SCIENCE, Issue 7 2007
Tomoo Ohashi
Abstract We have experimentally studied the fluorescence resonance energy transfer (FRET) between green fluorescent protein (GFP) molecules by inserting folded or intrinsically unstructured proteins between CyPet and Ypet. We discovered that most of the enhanced FRET signal previously reported for this pair was due to enhanced dimerization, so we engineered a monomerizing mutation into each. An insert containing a single fibronectin type III domain (3.7 nm end-to-end) gave a moderate FRET signal while a two-domain insert (7.0 nm) gave no FRET. We then tested unstructured proteins of various lengths, including the charged-plus-PQ domain of ZipA, the tail domain of ,-adducin, and the C-terminal tail domain of FtsZ. The structures of these FRET constructs were also studied by electron microscopy and sedimentation. A 12 amino acid linker and the N-terminal 33 amino acids of the charged domain of the ZipA gave strong FRET signals. The C-terminal 33 amino acids of the PQ domain of the ZipA and several unstructured proteins with 66,68 amino acids gave moderate FRET signals. The 150 amino acid charged-plus-PQ construct gave a barely detectable FRET signal. FRET efficiency was calculated from the decreased donor emission to estimate the distance between donor and acceptor. The donor,acceptor distance varied for unstructured inserts of the same length, suggesting that they had variable stiffness (persistence length). We conclude that GFP-based FRET can be useful for studying intrinsically unstructured proteins, and we present a range of calibrated protein inserts to experimentally determine the distances that can be studied. [source]

Crystallization and preliminary X-ray analysis of the C-terminal RNase III domain of human Dicer

ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 4 2006
Daijiro Takeshita
Human Dicer protein contains two RNase III domains (RNase IIIa and RNase IIIb) which are involved in the production of short interfering RNAs (siRNAs). The C-terminal RNase III domain (RNase IIIb) of human Dicer was expressed, purified and crystallized by the sitting-drop vapour-diffusion method. The crystals belonged to space group C2221, with unit-cell parameters a = 88.6, b = 199.7, c = 119.6,Å, and diffracted X-rays to 2.0,Å resolution. The asymmetric unit contained three molecules of the RNase IIIb and the solvent content was 67%. [source]

Solution structure of a late embryogenesis abundant protein (LEA14) from Arabidopsis thaliana, a cellular stress-related protein

PROTEIN SCIENCE, Issue 10 2005
Shanteri Singh
Abstract We report the three-dimensional structure of a late embryogenesis abundant (LEA) protein from Arabidopsis thaliana gene At1g01470.1. This protein is a member of Pfam cluster PF03168, and has been classified as a LEA14 protein. LEA proteins are expressed under conditions of cellular stress, such as desiccation, cold, osmotic stress, and heat. The structure, which was determined by NMR spectroscopy, revealed that the At1g01470.1 protein has an ,,-fold consisting of one ,-helix and seven ,-strands that form two antiparallel ,-sheets. The closest structural homologs were discovered to be fibronectin Type III domains, which have <7% sequence identity. Because fibronectins from animal cells have been shown to be involved in cell adhesion, cell motility, wound healing, and maintenance of cell shape, it is interesting to note that in plants wounding or stress results in the overexpression of a protein with fibronectin Type III structural features. [source]

Structure of the Calx-, domain of the integrin ,4 subunit: insights into function and cation-independent stability

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 8 2009
Noelia Alonso-García
The integrin ,6,4 is a receptor for laminins and provides stable adhesion of epithelial cells to the basement membranes. In addition, ,6,4 is important for keratinocyte migration during wound healing and favours the invasion of carcinomas into surrounding tissue. The cytoplasmic domain of the ,4 subunit is responsible for most of the intracellular interactions of the integrin; it contains four fibronectin type III domains and a Calx-, motif. The crystal structure of the Calx-, domain of ,4 was determined to 1.48,Å resolution. The structure does not contain cations and biophysical data support the supposition that the Calx-, domain of ,4 does not bind calcium. Comparison of the Calx-, domain of ,4 with the calcium-binding domains of Na+/Ca2+ -exchanger 1 reveals that in ,4 Arg1003 occupies a position equivalent to that of the calcium ions in the Na+/Ca2+ -exchanger. By combining mutagenesis and thermally induced unfolding, it is shown that Arg1003 contributes to the stability of the Calx-, domain. The structure of the Calx-, domain is discussed in the context of the function and intracellular interactions of the integrin ,4 subunit and a putative functional site is proposed. [source]