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Leucine-rich Repeat Protein (leucine-rich + repeat_protein)
Selected AbstractsNeuronal leucine-rich repeat 6 (XlNLRR-6) is required for late lens and retina development in Xenopus laevisDEVELOPMENTAL DYNAMICS, Issue 4 2006Adam D. Wolfe Abstract Leucine-rich repeat proteins expressed in the developing vertebrate nervous system comprise a complex, multifamily group, and little is known of their developmental function in vivo. We have identified a novel member of this group in Xenopus laevis, XlNLRR-6, and through sequence and phylogenetic analysis, have placed it within a defined family of vertebrate neuronal leucine-rich repeat proteins (NLRR). XlNLRR-6 is expressed in the developing nervous system and tissues of the eye beginning at the neural plate stage, and expression continues throughout embryonic and larval development. Using antisense morpholino oligonucleotide (MO) -mediated knockdown of XlNLRR-6, we demonstrate that this protein is critical for development of the lens, retina, and cornea. Reciprocal transplantation of presumptive lens ectoderm between MO-treated and untreated embryos demonstrate that XlNLRR-6 plays autonomous roles in the development of both the lens and retina. These findings represent the first in vivo functional analysis of an NLRR family protein and establish a role for this protein during late differentiation of tissues in the developing eye. Developmental Dynamics 235:1027,1041, 2006. © 2006 Wiley-Liss, Inc. [source] Leucine-rich repeat proteins of synapsesJOURNAL OF NEUROSCIENCE RESEARCH, Issue 13 2007Jaewon Ko Abstract Leucine-rich repeats (LRRs) are 20,29-aa motifs that mediate protein,protein interactions and are present in a variety of membrane and cytoplasmic proteins. Many LRR proteins with neuronal functions have been reported. Here, we summarize an emerging group of synaptic LRR proteins, which includes densin-180, Erbin, NGL, SALM, and LGI1. These proteins have been implicated in the formation, differentiation, maintenance, and plasticity of neuronal synapses. © 2007 Wiley-Liss, Inc. [source] Molecular characterization of Ciona sperm outer arm dynein reveals multiple components related to outer arm docking complex protein 2CYTOSKELETON, Issue 10 2006Akiko Hozumi Abstract Using proteomic and immunochemical techniques, we have identified the light and intermediate chains (IC) of outer arm dynein from sperm axonemes of the ascidian Cionaintestinalis. Ciona outer arm dynein contains six light chains (LC) including a leucine-rich repeat protein, Tctex1- and Tctex2-related proteins, a protein similar to Drosophila roadblock and two components related to Chlamydomonas LC8. No LC with thioredoxin domains is included in Ciona outer arm dynein. Among the five ICs in Ciona, three are orthologs of those in sea urchin dynein: two are WD-repeat proteins and the third one, unique to metazoan sperm flagella, contains both thioredoxin and nucleoside diphosphate kinase modules. The remaining two Ciona ICs have extensive coiled coil structure and show sequence similarity to outer arm dynein docking complex protein 2 (DC2) that was first identified in Chlamydomonas flagella. We recently identified a third DC2-like protein with coiled coil structure, Ci-Axp66.0 that is also associated in substoichiometric amounts with Ciona outer arm dynein. In addition, Oda5p, a component of an additional complex required for assembly of outer arm dynein in Chlamydomonas flagella, also groups with this family of DC2-like proteins. Thus, the assembly of outer arm dynein onto doublet microtubules involves multiple coiled-coil proteins related to DC2. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source] LRRN6A/LERN1 (leucine-rich repeat neuronal protein 1), a novel gene with enriched expression in limbic system and neocortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2003Laura Carim-Todd Abstract Human chromosome 15q24-q26 is a very complex genomic region containing several blocks of segmental duplications to which susceptibility to anxiety disorders has been mapped (Gratacos et al., 2001, Cell, 106, 367,379; Pujana et al., 2001, Genome Res., 11, 98,111). Through an in silico gene content analysis of the 15q24-q26 region we have identifie1d a novel gene, LRRN6A (leucine-rich repeat neuronal 6A), and confirmed its location to the centromeric end of this complex region. LRRN6A encodes a transmembrane leucine-rich repeat protein, LERN1 (leucine-rich repeat neuronal protein 1), with similarity to proteins involved in axonal guidance and migration, nervous system development and regeneration processes. The identification of homologous genes to LRRN6A on chromosomes 9 and 19 and the orthologous genes in the mouse genome and other organisms suggests that LERN proteins constitute a novel subfamily of LRR (leucine-rich repeat)-containing proteins. The LRRN6A expression pattern is specific to the central nervous system, highly and broadly expressed during early stages of development and gradually restricted to forebrain structures as development proceeds. Expression level in adulthood is lower in general but remains stable and significantly enriched in the limbic system and cerebral cortex. Taken together, the confirmation of LRRN6A's expression profile, its predicted protein structure and its similarity to nervous system-expressed LRR proteins with essential roles in nervous system development and maintenance suggest that LRRN6A is a novel gene of relevance in the molecular and cellular neurobiology of vertebrates. [source] Mesenchymal stem cells derived from synovium, meniscus, anterior cruciate ligament, and articular chondrocytes share similar gene expression profilesJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2009Yuko Segawa Abstract Mesenchymal stem cells (MSCs) can be obtained from various tissues, and contain common features. However, an increasing number of reports have described variant properties dependent of cell sources. We examined (1) whether MSCs existed in several intraarticular tissues, (2) whether gene expression profiles in intraarticular tissue MSCs closely resembled each other, and (3) whether identified genes were specific to intraarticular tissue MSCs. Human synovium, meniscus, intraarticular ligament, muscle, adipose tissue, and bone marrow were harvested, and colony-forming cells were analyzed. All these cells showed multipotentiality and surface markers typical of MSCs. Gene profiles of intraarticular tissue MSCs and chondrocytes were closer to each other than those of extraarticular tissues MSCs. Among three characteristic genes specific for intraarticular tissue MSCs, we focused on proline arginine-rich end leucine-rich repeat protein (PRELP). Higher expression of PRELP was confirmed in chondrocytes and intraarticular tissue MSCs among three elderly and three young donors. Synovium MSCs stably expressed PRELP, contrarily, bone marrow MSCs increased PRELP expression during in vitro chondrogenesis. In conclusion, MSCs could be isolated from various intraarticular tissues including meniscus and ligament, gene expression profiles of intraarticular tissue MSCs closely resembled each other, and the higher expression of PRELP was characteristic of intraarticular tissue MSCs. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 435,441, 2009 [source] A leucine-rich repeat protein is required for growth promotion and enhanced seed production mediated by the endophytic fungus Piriformospora indica in Arabidopsis thalianaTHE PLANT JOURNAL, Issue 1 2007Bationa Shahollari Summary Piriformospora indica, a basidiomycete of the Sebacinaceae family, promotes the growth, development and seed production of a variety of plant species. Arabidopsis plants colonized with the fungus produce 22% more seeds than uncolonized plants. Deactivating the Arabidopsis single-copy gene DMI-1, which encodes an ion carrier required for mycorrihiza formation in legumes, does not affect the beneficial interaction between the two symbiotic partners. We used cellular and molecular responses initiated during the establishment of the interaction between P. indica and Arabidopsis roots to isolate mutants that fail to respond to the fungus. An ethylmethane sulfonate mutant (Piriformospora indica - insensitive-2; pii-2), and a corresponding insertion line, are impaired in a leucine-rich repeat protein (At1g13230). The protein pii-2, which contains a putative endoplasmic reticulum retention signal, is also found in Triton X-100-insoluble plasma membrane microdomains, suggesting that it is present in the endoplasmic reticulum/plasma membrane continuum in Arabidopsis roots. The microdomains also contain an atypical receptor protein (At5g16590) containing leucine-rich repeats, the message of which is transiently upregulated in Arabidopsis roots in response to P. indica. This response is not detectable in At1g13230 mutants, and the protein is not detectable in the At1g13230 mutant microdomains. Partial deactivation of a gene for a sphingosine kinase, which is required for the biosynthesis of sphingolipid found in plasma membrane microdomains, also affects the Arabidopsis/P. indica interaction. Thus, pii-2, and presumably also At5g16590, two proteins present in plasma membrane microdomains, appear to be involved in P. indica -induced growth promotion and enhanced seed production in Arabidopsis thaliana. [source] Neuronal leucine-rich repeat 6 (XlNLRR-6) is required for late lens and retina development in Xenopus laevisDEVELOPMENTAL DYNAMICS, Issue 4 2006Adam D. Wolfe Abstract Leucine-rich repeat proteins expressed in the developing vertebrate nervous system comprise a complex, multifamily group, and little is known of their developmental function in vivo. We have identified a novel member of this group in Xenopus laevis, XlNLRR-6, and through sequence and phylogenetic analysis, have placed it within a defined family of vertebrate neuronal leucine-rich repeat proteins (NLRR). XlNLRR-6 is expressed in the developing nervous system and tissues of the eye beginning at the neural plate stage, and expression continues throughout embryonic and larval development. Using antisense morpholino oligonucleotide (MO) -mediated knockdown of XlNLRR-6, we demonstrate that this protein is critical for development of the lens, retina, and cornea. Reciprocal transplantation of presumptive lens ectoderm between MO-treated and untreated embryos demonstrate that XlNLRR-6 plays autonomous roles in the development of both the lens and retina. These findings represent the first in vivo functional analysis of an NLRR family protein and establish a role for this protein during late differentiation of tissues in the developing eye. Developmental Dynamics 235:1027,1041, 2006. © 2006 Wiley-Liss, Inc. [source] | ||||||||||