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Domain Consisting (domain + consisting)
Selected AbstractsEffect of mutations in the ,5,,7 loop on the structure and properties of human small heat shock protein HSP22 (HspB8, H11)FEBS JOURNAL, Issue 21 2007Alexei S. Kasakov The human genome encodes ten different small heat shock proteins, each of which contains the so-called ,-crystallin domain consisting of 80,100 residues and located in the C-terminal part of the molecule. The ,-crystallin domain consists of six or seven ,-strands connected by different size loops and combined in two ,-sheets. Mutations in the loop connecting the ,5 and ,7 strands and conservative residues of ,7 in ,A-, ,B-crystallin and HSP27 correlate with the development of different congenital diseases. To understand the role of this part of molecule in the structure and function of small heat shock proteins, we mutated two highly conservative residues (K137 and K141) of human HSP22 and investigated the properties of the K137E and K137,141E mutants. These mutations lead to a decrease in intrinsic Trp fluorescence and the double mutation decreased fluorescence resonance energy transfer from Trp to bis-ANS bound to HSP22. Mutations K137E and especially K137,141E lead to an increase in unordered structure in HSP22 and increased susceptibility to trypsinolysis. Both mutations decreased the probability of dissociation of small oligomers of HSP22, and mutation K137E increased the probability of HSP22 crosslinking. The wild-type HSP22 possessed higher chaperone-like activity than their mutants when insulin or rhodanase were used as the model substrates. Because conservative Lys residues located in the ,5,,7 loop and in the ,7 strand appear to play an important role in the structure and properties of HSP22, mutations in this part of the small heat shock protein molecule might have a deleterious effect and often correlate with the development of different congenital diseases. [source] Cloning, chromosomal localization and characterization of the murine mucin gene orthologous to human MUC4FEBS JOURNAL, Issue 13 2002Jean-Luc Desseyn We report here the full coding sequence of a novel mouse putative membrane-associated mucin containing three extracellular EGF-like motifs and a mucin-like domain consisting of at least 20 tandem repeats of 124,126 amino acids. Screening a cosmid and a BAC libraries allowed to isolate several genomic clones. Genomic and cDNA sequence comparisons showed that the gene consists of 25 exons and 24 introns covering a genomic region of ,,52 kb. The first intron is ,,16 kb in length and is followed by an unusually large exon (, 9.5 kb) encoding Ser/Thr-rich tandemly repeated sequences. Radiation hybrid mapping localized this new gene to a mouse region of chromosome 16, which is the orthologous region of human chromosome 3q29 encompassing the large membrane-anchored mucin MUC4. Contigs analysis of the Human Genome Project did not reveal any other mucin on chromosome 3q29 and, interestingly, our analysis allowed the determination of the genomic organization of the human MUC4 and showed that its exon/intron structure is identical to that of the mouse gene we cloned. Furthermore, the human MUC4 shares considerable homologies with the mouse gene. Based on these data, we concluded that we isolated the mouse ortholog of MUC4 we propose as Muc4. Expression studies showed that Muc4 is ubiquitous like SMC and MUC4, with highest levels of expression in trachea and intestinal tract. [source] Crystal structure of an enhancer of rudimentary homolog (ERH) at 2.1 Å resolutionPROTEIN SCIENCE, Issue 7 2005Ryoichi Arai Abstract The enhancer of rudimentary gene, e(r), of Drosophila melanogaster encodes an enhancer of rudimentary (ER) protein with functions implicated in pyrimidine biosynthesis and the cell cycle. The ER homolog (ERH) is highly conserved among vertebrates, invertebrates, and plants. Xenopus laevis ERH was reported to be a transcriptional repressor. Here we report the 2.1 Å crystal structure of murine ERH (Protein Data Bank ID 1WZ7), determined by the multiwavelength anomalous dispersion (MAD) method. The monomeric structure of ERH comprises a single domain consisting of three ,-helices and four ,-strands, which is a novel fold. In the crystal structure, ERH assumes a dimeric structure, through interactions between the ,-sheet regions. The formation of an ERH dimer is consistent with the results of analytical ultracentrifugation. The residues at the core region and at the dimer interface are highly conserved, suggesting the conservation of the dimer formation as well as the monomer fold. The long flexible loop (44,53) is also significantly conserved, suggesting that this loop region may be important for the functions of ERH. In addition, the putative phosphorylation sites are located at the start of the ,2-strand (Thr18) and at the start of the ,1-helix (Ser24), implying that the phosphorylation might cause some structural changes. [source] Determining the DUF55-domain structure of human thymocyte nuclear protein 1 from crystals partially twinned by tetartohedryACTA CRYSTALLOGRAPHICA SECTION D, Issue 3 2009Feng Yu Human thymocyte nuclear protein 1 contains a unique DUF55 domain consisting of 167 residues (55,221), but its cellular function remains unclear. Crystals of DUF55 belonged to the trigonal space group P31, but twinning caused the data to approach apparent 622 symmetry. Two data sets were collected to 2.3,Å resolution. Statistical analysis confirmed that both data sets were partially twinned by tetartohedry. Tetartohedral twin fractions were estimated. After the structure had been determined, only one twofold axis of rotational pseudosymmetry was found in the crystal structure. Using the DALI program, a YTH domain, which is a potential RNA-binding domain from human YTH-domain-containing protein 2, was identified as having the most similar three-dimensional fold to that of DUF55. It is thus implied that DUF55 might be a potential RNA-related domain. [source] Crystallization of the proline-rich-peptide binding domain of human type I collagen prolyl 4-hydroxylaseACTA CRYSTALLOGRAPHICA SECTION D, Issue 5 2003Mira Pekkala Collagen prolyl 4-hydroxylases catalyze the hydroxylation of -X -Pro-Gly- sequences and play an essential role in the synthesis of all collagens. They require Fe2+, 2-oxoglutarate, molecular oxygen and ascorbate, and all vertebrate collagen prolyl 4-hydroxylases are ,2,2 tetramers. The ,-subunits contain separate catalytic and peptide substrate-binding domains. Here, the crystallization of the peptide substrate-binding domain consisting of residues 144,244 of the 517-residue human ,(I) subunit is described. The crystals are well ordered and diffract to at least 3,Å. The space group is P31 or P32 and the asymmetric unit most probably contains a dimer. [source] | ||||||||||