Nakazawa T

References (4)

Title : An Autism-Associated Neuroligin-3 Mutation Affects Developmental Synapse Elimination in the Cerebellum - Lai_2021_Front.Neural.Circuits_15_676891
Author(s) : Lai ESK , Nakayama H , Miyazaki T , Nakazawa T , Tabuchi K , Hashimoto K , Watanabe M , Kano M
Ref : Front Neural Circuits , 15 :676891 , 2021
Abstract : Neuroligin is a postsynaptic cell-adhesion molecule that is involved in synapse formation and maturation by interacting with presynaptic neurexin. Mutations in neuroligin genes, including the arginine to cystein substitution at the 451st amino acid residue (R451C) of neuroligin-3 (NLGN3), have been identified in patients with autism spectrum disorder (ASD). Functional magnetic resonance imaging and examination of post-mortem brain in ASD patients implicate alteration of cerebellar morphology and Purkinje cell (PC) loss. In the present study, we examined possible association between the R451C mutation in NLGN3 and synaptic development and function in the mouse cerebellum. In NLGN3-R451C mutant mice, the expression of NLGN3 protein in the cerebellum was reduced to about 10% of the level of wild-type mice. Elimination of redundant climbing fiber (CF) to PC synapses was impaired from postnatal day 10-15 (P10-15) in NLGN3-R451C mutant mice, but majority of PCs became mono-innervated as in wild-type mice after P16. In NLGN3-R451C mutant mice, selective strengthening of a single CF relative to the other CFs in each PC was impaired from P16, which persisted into juvenile stage. Furthermore, the inhibition to excitation (I/E) balance of synaptic inputs to PCs was elevated, and calcium transients in the soma induced by strong and weak CF inputs were reduced in NLGN3-R451C mutant mice. These results suggest that a single point mutation in NLGN3 significantly influences the synapse development and refinement in cerebellar circuitry, which might be related to the pathogenesis of ASD.
ESTHER : Lai_2021_Front.Neural.Circuits_15_676891
PubMedSearch : Lai_2021_Front.Neural.Circuits_15_676891
PubMedID: 34262438
Gene_locus related to this paper: human-NLGN3

Title : Genome sequences of 65 Helicobacter pylori strains isolated from asymptomatic individuals and patients with gastric cancer, peptic ulcer disease, or gastritis - Blanchard_2013_Pathog.Dis_68_39
Author(s) : Blanchard TG , Czinn SJ , Correa P , Nakazawa T , Keelan M , Morningstar L , Santana-Cruz I , Maroo A , McCracken C , Shefchek K , Daugherty S , Song Y , Fraser CM , Fricke WF
Ref : Pathog Dis , 68 :39 , 2013
Abstract : Helicobacter pylori, inhabitant of the gastric mucosa of over half of the world population, with decreasing prevalence in the U.S., has been associated with a variety of gastric pathologies. However, the majority of H. pylori-infected individuals remain asymptomatic, and negative correlations between H. pylori and allergic diseases have been reported. Comprehensive genome characterization of H. pylori populations from different human host backgrounds including healthy individuals provides the exciting potential to generate new insights into the open question whether human health outcome is associated with specific H. pylori genotypes or dependent on other environmental factors. We report the genome sequences of 65 H. pylori isolates from individuals with gastric cancer, preneoplastic lesions, peptic ulcer disease, gastritis, and from asymptomatic adults. Isolates were collected from multiple locations in North America (USA and Canada) as well as from Columbia and Japan. The availability of these H. pylori genome sequences from individuals with distinct clinical presentations provides the research community with a resource for detailed investigations into genetic elements that correlate either positively or negatively with the epidemiology, human host adaptation, and gastric pathogenesis and will aid in the characterization of strains that may favor the development of specific pathology, including gastric cancer.
ESTHER : Blanchard_2013_Pathog.Dis_68_39
PubMedSearch : Blanchard_2013_Pathog.Dis_68_39
PubMedID: 23661595
Gene_locus related to this paper: helpy-o25061

Title : Comparison of whole genome sequences of Chlamydia pneumoniae J138 from Japan and CWL029 from USA - Shirai_2000_Nucleic.Acids.Res_28_2311
Author(s) : Shirai M , Hirakawa H , Kimoto M , Tabuchi M , Kishi F , Ouchi K , Shiba T , Ishii K , Hattori M , Kuhara S , Nakazawa T
Ref : Nucleic Acids Research , 28 :2311 , 2000
Abstract : Chlamydia pneumoniae is a widespread pathogen of humans causing pneumonia and bronchitis. There are many reports of an association between C.PNEUMONIAE: infection and atherosclerosis. We determined the whole genome sequence of C.PNEUMONIAE: strain J138 isolated in Japan in 1994 and compared it with the sequence of strain CWL029 isolated in the USA before 1987. The J138 circular chromosome consists of 1 226 565 nt (40.7% G+C) with 1072 likely protein-coding genes that is 3665 nt shorter than the CWL029 genome. Plasmids, phage- or transposon-like sequences were not identified. The overall genomic organization, gene order and predicted proteomes of the two strains are very similar, suggesting a high level of structural and functional conservation between the two unrelated isolates. The most conspicuous differences in the J138 genome relative to the CWL029 genome are the absence of five DNA segments, ranging in size from 89 to 1649 nt, and the presence of three DNA segments, ranging from 27 to 84 nt. The complex organization of these 'different zones' may be attributable to a unique system of recombination.
ESTHER : Shirai_2000_Nucleic.Acids.Res_28_2311
PubMedSearch : Shirai_2000_Nucleic.Acids.Res_28_2311
PubMedID: 10871362
Gene_locus related to this paper: chlpn-CPJ0152 , chlpn-CPJ0342 , chlpn-CPN0161 , chlpn-CPN0271 , chlpn-q9jrv1 , chlpn-q9js10 , chlpn-q9k1u7 , chlpn-q9z6x9

Title : Apparent dipeptidyl peptidase activities of acylamino acid-releasing enzymes - Tsunasawa_1983_J.Biochem.(Tokyo)_93_1217
Author(s) : Tsunasawa S , Imanaka T , Nakazawa T
Ref : J Biochem (Tokyo) , 93 :1217 , 1983
Abstract : An acylamino acid-releasing enzyme purified from porcine liver showed peptidase activity above pH 8. Of the non-acylated peptides tested, this peptidase activity was only exerted on peptides with Gly or Ala at their N-termini. These results are consistent with the previous observations for similar enzymes from sheep red blood cells (Witheiler, J. & Wilson, D.B. (1972) J. Biol. Chem. 247, 2217-2221) and beef liver (Gade, W. & Brown, J.L. (1978) J. Biol. Chem. 253, 5012-5018). The pH dependence of the peptidase activity showed that only peptides with uncharged N-terminal amino acids such as glycyl- or alanyl-peptides act as substrates for the enzyme. These results suggest that the peptidase activity seen for the acylamino acid-releasing enzyme is an intrinsic activity of the enzyme that is triggered by misrecognition of uncharged smaller N-terminal amino acids in non-acylated peptides as acyl groups at higher pHs.
ESTHER : Tsunasawa_1983_J.Biochem.(Tokyo)_93_1217
PubMedSearch : Tsunasawa_1983_J.Biochem.(Tokyo)_93_1217
PubMedID: 6345518