共查询到20条相似文献,搜索用时 15 毫秒
1.
Yuzaki M 《Cellular and molecular life sciences : CMLS》2008,65(11):1698-1705
The C1q family is characterized by a C-terminal conserved global C1q domain, which is structurally very similar to the tumor necrosis factor homology domain. Although some C1q family members are expressed in the central nervous system, their functions have not been well characterized. Cbln1, a member of the Cbln subfamily of the C1q family, is predominantly expressed in cerebellar granule cells. Interestingly, Cbln1 was recently shown to play two unique roles at excitatory synapses formed between cerebellar granule cells and Purkinje cells: the formation and stabilization of synaptic contact, and the control of functional synaptic plasticity by regulating the postsynaptic endocytosis pathway. Since other Cbln subfamily members, Cbln2-Cbln4, are expressed in various regions of developing and mature brains, Cbln subfamily proteins may generally serve as a new class of transneuronal regulators of synapse development and synaptic plasticity in various brain regions. 相似文献
2.
Matricellular proteins interact with the extracellular matrix (ECM) and modulate cellular processes by binding to cell surface receptors and initiating intracellular signal transduction. Their association with the ECM and the ability of some members of this protein family to regulate cell motility have opened up new avenues of research to investigate their functions in normal and diseased cells. In this review, we summarize the research on CyrA, an ECM calmodulin-binding protein in Dictyostelium. CyrA is proteolytically cleaved into smaller EGF-like (EGFL) repeat containing cleavage products during development. The first EGFL repeat of CyrA binds to the cell surface and activates a novel signalling pathway that modulates cell motility in this model organism. The similarity of CyrA to the most well-characterized matricellular proteins in mammals allows it to be designated as the first matricellular protein identified in Dictyostelium. 相似文献
3.
Y. Sugano 《Cellular and molecular life sciences : CMLS》2009,66(8):1387-1403
Dye-decolorizing peroxidase (DyP) is produced by a basidiomycete (Thanatephorus cucumeris Dec 1) and is a member of a novel heme peroxidase family (DyP-type peroxidase family) that appears to be distinct from general
peroxidases. Thus far, 80 putative members of this family have been registered in the PeroxiBase database (http://peroxibase.isbsib.ch/)
and more than 400 homologous proteins have been detected via PSI-BLAST search. Although few studies have characterized the
function and structure of these proteins, they appear to be bifunctional enzymes with hydrolase or oxygenase, as well as typical
peroxidase activities. DyP-type peroxidase family suggests an ancient root compared with other general peroxidases because
of their widespread distribution in the living world. In this review, firstly, an outline of the characteristics of DyP from
T. cucumeris is presented and then interesting characteristics of the DyP-type peroxidase family are discussed.
Received 14 October 2008; received after revision 12 November 2008; accepted 17 November 2008 相似文献
4.
Ismail Sahin Gul Paco Hulpiau Yvan Saeys Frans van Roy 《Cellular and molecular life sciences : CMLS》2017,74(3):525-541
The superfamily of armadillo repeat proteins is a fascinating archetype of modular-binding proteins involved in various fundamental cellular processes, including cell–cell adhesion, cytoskeletal organization, nuclear import, and molecular signaling. Despite their diverse functions, they all share tandem armadillo (ARM) repeats, which stack together to form a conserved three-dimensional structure. This superhelical armadillo structure enables them to interact with distinct partners by wrapping around them. Despite the important functional roles of this superfamily, a comprehensive analysis of the composition, classification, and phylogeny of this protein superfamily has not been reported. Furthermore, relatively little is known about a subset of ARM proteins, and some of the current annotations of armadillo repeats are incomplete or incorrect, often due to high similarity with HEAT repeats. We identified the entire armadillo repeat superfamily repertoire in the human genome, annotated each armadillo repeat, and performed an extensive evolutionary analysis of the armadillo repeat proteins in both metazoan and premetazoan species. Phylogenetic analyses of the superfamily classified them into several discrete branches with members showing significant sequence homology, and often also related functions. Interestingly, the phylogenetic structure of the superfamily revealed that about 30 % of the members predate metazoans and represent an ancient subset, which is gradually evolving to acquire complex and highly diverse functions. 相似文献
5.
Snake venom thrombin-like enzymes: from reptilase to now 总被引:12,自引:0,他引:12
Castro HC Zingali RB Albuquerque MG Pujol-Luz M Rodrigues CR 《Cellular and molecular life sciences : CMLS》2004,61(7-8):843-856
The snake venom thrombin-like enzymes (SVTLEs) comprise a number of serine proteases functionally and structurally related to thrombin. Until recently, only nine complete sequences of this subgroup of the serine protease family were known. Over the past 5 years, the primary structure of several SVTLEs has been characterized, and now this family includes several members. Of particular interest is their possible use in pathologies such as thrombosis. The aim of the present review is to summarize the state of the art concerning the evolutionary, structural and biological features of the SVTLEs.Received 16 August 2003; received after revision 26 September 2003; accepted 1 October 2003 相似文献
6.
Matthew D. Hitchings Philip Townsend Ehmke Pohl Paul D. Facey D. Hugh Jones Paul J. Dyson Ricardo Del Sol 《Cellular and molecular life sciences : CMLS》2014,71(24):4911-4926
Dps proteins are members of an extensive family of proteins that oxidise and deposit iron in the form of ferric oxide, and are also able to bind DNA. Ferroxidation centres are formed at the interface of anti-parallel dimers, which further assemble into dodecameric nanocages with a hollow core where ferric oxide is deposited. Streptomyces coelicolor encodes three Dps-like proteins (DpsA, B and C). Despite sharing the conserved four-helix bundle organisation observed in members of the Dps family, they display significant differences in the length of terminal extensions, or tails. DpsA possess both N- and C-terminal tails of different lengths, and their removal affects quaternary structure assembly to varying degrees. DpsC quaternary structure, on the other hand, is heavily dependent on its N-terminal tail as its removal abolishes correct protein folding. Analysis of the crystal structure of dodecamers from both proteins revealed remarkable differences in the position of tails and interface surface area; and provides insight to explain the differences in biochemical behaviour observed while comparing DpsA and DpsC. 相似文献
7.
8.
François Bernier 《Cellular and molecular life sciences : CMLS》2013,70(17):3045-3056
DING proteins, named after their conserved N-terminus, form an overlooked protein family whose members were generally discovered through serendipity. It is characterized by an unusually high sequence conservation, even between distantly related species, and by an outstanding diversity of activities and ligands. They all share a demonstrated capacity to bind phosphate with high affinity or at least a predicted phosphate-binding site. However, DING protein genes are conspicuously absent from databases. The many novel family members identified in recent years have confirmed that DING proteins are ubiquitous not only in animals and plants but probably also in prokaryotes. At the functional level, there is increasing evidence that they participate in many health-related processes such as cancers as well as bacterial (Pseudomonas) and viral (HIV) infections, by mechanisms that are now beginning to be understood. They thus represent potent targets for the development of novel therapeutic approaches, especially against HIV. The few genomic sequences that are now available are starting to give some clues on why DING protein genes and mRNAs are well conserved and difficult to clone. This could open a new era of research, of both fundamental and applied importance. 相似文献
9.
Lecticans: organizers of the brain extracellular matrix 总被引:19,自引:0,他引:19
Yamaguchi Y 《Cellular and molecular life sciences : CMLS》2000,57(2):276-289
Lecticans are a family of chondroitin sulfate proteoglycans, encompassing aggrecan, versican, neurocan and brevican. These
proteoglycans are characterized by the presence of ahyaluronan-binding domain and a C-type lectin domain in their core proteins.
Through these domains, lecticans interact with carbohydrate and protein ligands in the extracellular matrix and act as linkers
of these extracellular matrix molecules. In adult brain, lecticans are thought to interact with hyaluronan and tenascin-R
to form a ternary complex. We propose that the hyaluronan-lectican-tenascin-R complex constitutes the core assembly of the
adult brain extracellular matrix, which is found mainly in pericellular spaces of neurons as ‘perineuronal nets’.
Received 27 September 1999; accepted 26 October 1999 相似文献
10.
Carboxypeptidases from A to Z: implications in embryonic development and Wnt binding 总被引:4,自引:0,他引:4
Carboxypeptidases perform many diverse functions in the body. The well-studied pancreatic enzymes (carboxypeptidases A1, A2 and B) are involved in the digestion of food, whereas a related enzyme (mast-cell carboxypeptidase A) functions in the degradation of other proteins. Several members of the metallocarboxypeptidase gene family (carboxypeptidases D, E, M and N) are more selective enzymes and are thought to play a role in the processing of intercellular peptide messengers. Three other members of the metallocarboxypeptidase gene family do not appear to encode active enzymes; these members have been designated CPX-1, CPX-2 and AEBP1/ACLP. In this review, we focus on the recently discovered carboxypeptidase Z (CPZ). This enzyme removes C-terminal Arg residues from synthetic substrates, as do many of the other members of the gene family. However, CPZ differs from the other enzymes in that CPZ is enriched in the extracellular matrix and is broadly distributed during early embryogenesis. In addition to containing a metallocarboxypeptidase domain, CPZ also contains a Cys-rich domain that has homology to Wnt-binding proteins; Wnts are important signaling molecules during development. Although the exact function of CPZ is not yet known, it is likely that this protein plays a role in development by one of several possible mechanisms. 相似文献
11.
Kank proteins: structure, functions and diseases 总被引:1,自引:1,他引:0
N. Kakinuma Y. Zhu Y. Wang B. C. Roy R. Kiyama 《Cellular and molecular life sciences : CMLS》2009,66(16):2651-2659
The Kank family of proteins, Kank1–Kank4, are characterized by their unique structure, coiled-coil motifs in the N-terminal
region, and ankyrin-repeats in the C-terminal region, with an additional motif, the KN motif, at the N-terminus. Kank1 was obtained by positional cloning of a tumor suppressor gene in renal cell carcinoma, while the other members were found
by homology search. The family is involved in the regulation of actin polymerization and cell motility through signaling pathways
containing PI3K/Akt and/or unidentified modulators/effectors. Their relationship to diseases such as cancer, and to neuronal
and developmental disorders, will be an important subject of future study. 相似文献
12.
New mitochondrial carriers: an overview 总被引:4,自引:0,他引:4
The transport of metabolites, nucleotides and cofactors across the mitochondrial inner membrane is performed by members of mitochondrial carrier family (MCF). These proteins share marked structural features that have made feasible the functional characterization of numerous MCs in the last years. The MCs responsible for transport activities in mitochondria known for decades such as glutamate uptake or ATP-Mg/Pi exchange have recently been identified as well as novel carriers such as those involved in S-adenosylmethionine or thiamine pyrophosphate uptake. Here, after a brief review of the novel data on structural characteristics and import mechanisms of MCF members, we present an exhaustive compilation of human MC sequences, including previously characterized carriers, together with their respective Saccharomyces cerevisiae orthologues, ordered according to the phylogenetic analysis of el Moualij and co-workers [Yeast (1997) 13: 573-581]. We have detected the existence of at least 49 human MC sequences, including those of yet unknown function. An overview of novel MCF members functionally characterized in recent years in mammals and in yeast genomes is presented. 相似文献
13.
Engen JR Wales TE Hochrein JM Meyn MA Banu Ozkan S Bahar I Smithgall TE 《Cellular and molecular life sciences : CMLS》2008,65(19):3058-3073
Src-family kinases are modular signaling proteins involved in a diverse array of cellular processes. All members of the Src
family share the same domain organization, with modular SH3, SH2 and kinase domains followed by a C-terminal negative regulatory
tail. X-ray crystallographic analyses of several Src family members have revealed critical roles for the SH3 and SH2 domains
in the down-regulation of the kinase domain. This review focuses on biological, biophysical, and computational studies that
reveal conformationally distinct active states within this unique kinase family.
Received 10 March 2008; received after revision 17 May 2008; accepted 21 May 2008 相似文献
14.
Shikanai T 《Cellular and molecular life sciences : CMLS》2006,63(6):698-708
In plants, RNA editing is a process for converting a specific nucleotide of RNA from C to U and less frequently from U to
C in mitochondria and plastids. To specify the site of editing, the cis-element adjacent to the editing site functions as a binding site for the trans-acting factor. Genetic approaches using Arabidopsis thaliana have clarified that a member of the protein family with pentatricopeptide repeat (PPR) motifs is essential for RNA editing
to generate a translational initiation codon of the chloroplast ndhD gene. The PPR motif is a highly degenerate unit of 35 amino acids and appears as tandem repeats in proteins that are involved
in RNA maturation steps in mitochondria and plastids. The Arabidopsis genome encodes approximately 450 members of the PPR family, some of which possibly function as trans-acting factors binding the cis-elements of the RNA editing sites to facilitate access of an unidentified RNA editing enzyme. Based on this breakthrough
in the research on plant RNA editing, I would like to discuss the possible steps of co-evolution of RNA editing events and
PPR proteins.
Received 30 September 2005; received after revision 5 November 2005; accepted 28 November 2005 相似文献
15.
Functions of fatty acid binding proteins 总被引:1,自引:0,他引:1
R. M. Kaikaus N. M. Bass R. K. Ockner 《Cellular and molecular life sciences : CMLS》1990,46(6):617-630
Summary Cytosolic fatty acid binding proteins (FABP) belong to a gene family of which eight members have been conclusively identified. These 14–15 kDa proteins are abundantly expressed in a highly tissue-specific manner. Although the functions of the cytosolic FABP are not clearly established, they appear to enhance the transfer of long-chain fatty acids between artificial and native lipid membranes, and also to have a stimulatory effect on a number of enzymes of fatty acid metabolism in vitro. These findings, as well as the tissue expression, ligand binding properties, ontogeny and regulation of these proteins provide a considerable body of indirect evidence supporting a broad role for the FABP in the intracellular transport and metabolism of long-chain fatty acids. The available data also support the existence of structure- and tissue-specific specialization of function among different members of the FABP gene family. Moreover, FABP may also have a possible role in the modulation of cell growth and proliferation, possibly by virtue of their affinity for ligands such as prostaglandins, leukotrienes and fatty acids, which are known to influence cell growth activity. FABP structurally unrelated to the cytosolic gene family have also been identified in the plasma membranes of several tissues (FABPpm). These proteins have not been fully characterized to date, but strong evidence suggests that they function in the transport of long-chain fatty acids across the plasma membrane. 相似文献
16.
The inhibitor of growth (ING) family of tumor suppressors has five members and is implicated in the control of apoptosis,
senescence, DNA repair, and cancer progression. However, little is known about ING activity in the regulation of cancer progression.
ING members and splice variants seem to behave differently with respect to cancer invasion and metastasis. Interaction with
histone trimethylated at lysine 4 (H3K4me3), hypoxia inducible factor-1 (HIF-1), p53, and nuclear factor kappa-B (NF-κB) are
potential mechanisms by which ING members exert effects on invasion and metastasis. Subcellular mislocalization, rapid protein
degradation, and to a lesser extent ING gene mutation are among the mechanisms responsible for inappropriate ING levels in cancer cells. The aim of this review is
to summarize the different roles of ING family tumor suppressors in cancer progression and the molecular mechanisms involved. 相似文献
17.
Functions of fatty acid binding proteins 总被引:7,自引:0,他引:7
Cytosolic fatty acid binding proteins (FABP) belong to a gene family of which eight members have been conclusively identified. These 14-15 kDa proteins are abundantly expressed in a highly tissue-specific manner. Although the functions of the cytosolic FABP are not clearly established, they appear to enhance the transfer of long-chain fatty acids between artificial and native lipid membranes, and also to have a stimulatory effect on a number of enzymes of fatty acid metabolism in vitro. These findings, as well as the tissue expression, ligand binding properties, ontogeny and regulation of these proteins provide a considerable body of indirect evidence supporting a broad role for the FABP in the intracellular transport and metabolism of long-chain fatty acids. The available data also support the existence of structure- and tissue-specific specialization of function among different members of the FABP gene family. Moreover, FABP may also have a possible role in the modulation of cell growth and proliferation, possibly by virtue of their affinity for ligands such as prostaglandins, leukotrienes and fatty acids, which are known to influence cell growth activity. FABP structurally unrelated to the cytosolic gene family have also been identified in the plasma membranes of several tissues (FABPpm). These proteins have not been fully characterized to date, but strong evidence suggest that they function in the transport of long-chain fatty acids across the plasma membrane. 相似文献
18.
OSBP (oxysterol-binding protein) and ORPs (OSBP-related proteins) constitute an enigmatic eukaryotic protein family that is
united by a signature domain that binds oxysterols, sterols, and possibly other hydrophobic ligands. The human genome contains
12 OSBP/ORP family members genes, while that of the budding yeast Saccharomyces cerevisiae encodes seven OSBP homologues (Osh). Of these, Osh4 (also referred to as Kes1) has been the most widely studied to date.
Recently, three-dimensional crystal structures of Osh4 with and without sterols bound within the core of the protein were
determined. The core consists of 19 anti-parallel β-sheets that form a near-complete β-barrel. Recent work has suggested that
Osh proteins facilitate the non-vesicular transport of sterols in vivo and in vitro, while other evidence supports a role for Osh proteins in the regulation of vesicular transport and lipid metabolism.This
article will review recent advances in the study of ORP/Osh proteins and will discuss future research issues regarding the
ORP/Osh family.
Received 17 July 2007; received after revision 14 August 2007; accepted 12 September 2007 相似文献
19.