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131.
Genomic organization, chromosomal localization and regulation of expression of the neuronal nuclear matrix protein NRP/B in human brain tumors 总被引:5,自引:0,他引:5
The nuclear matrix and its role in cell physiology are largely unknown, and the discovery of any matrix constituent whose expression is tissue- and/or cell-specific offers a new avenue of exploration. Studies of the novel neuronal nuclear matrix protein, NRP/B, reveal that it is an early and highly specific marker of neuronal induction and development in vertebrates, since its expression is restricted mainly to the developing and mature nervous system. These studies also show that NRP/B is involved in neuronal differentiation. To further examine the structure-function of NRP/B, we have cloned and characterized the murine Nrp/b gene. The murine gene consists of four exons interrupted by three introns that span 7.6kb of DNA. The complete open reading frame is localized in exon 3, suggesting that NRP/B is highly conserved during evolution. Chromosomal analysis shows that NRP/B is localized to chromosome 13 in mouse and chromosome 5q12-13 in human.Since our previous studies demonstrated that NRP/B is expressed in primary hippocampal neurons but not in primary astrocytes, we have characterized NRP/B mRNA and protein expression in various brain cell lines and in human brain tumors. Abundant expression of NRP/B mRNA and protein was observed in human neuroblastoma cell lines (IMR32, SKN-MC, SKN-SH), in glioblastoma cell lines (A172, T98G, U87-MG, U118-MG, U138-MG, and U373-MG), in neuroglioma (H4) and astrocytoma cell lines (CCF-STTG1 and SW1088). Confocal analysis of NRP/B in U87-MG glioblastoma cells indicated nuclear localization of NRP/B. NRP/B expression was also observed in human primary brain tumors including glioblastoma multiformae and astrocytomas (total of five cases). These results suggest that NRP/B expression is upregulated in human brain tumors including glioblastomas and astrocytomas, while under normal conditions NRP/B expression is restricted to neurons. This study implicates a role for NRP/B in brain tumor development. 相似文献
132.
We screened clones for thioredoxin reductase genes with a degenerate PCR-based strategy and have isolated two novel cDNA clones from a mouse thymocyte cDNA library. These encode two distinct thioredoxin reductases (TrxR1 and TrxR2) with 499 and 527 amino acid (aa) residues and calculated molecular masses of 54.5 kDa and 56.8 kDa respectively. These proteins share 90% and 50% aa sequence identity with those of previously cloned human TrxR, containing the redox-active cysteines, FAD binding domain, and the selenocysteine (SeCys) insertion sequence, which is composed of a putative stem-loop sequence located in the 3'-untranslated region (UTR). TrxR2 showing less homology to human TrxR has a mitochondrial translocation signal and a mitochondrial prepeptide protease cleavage site in the N-terminal domain. Transient expression experiments of each gene as fusion proteins with Xpress-tagged protein in NIH 3T3 cells indicated that TrxR1 was localized in the nucleus and cytoplasm and TrxR2 in the mitochondria. Furthermore, we mapped the TrxR1 gene to chromosome 10 (placed 1.71 cR from D10Mit42, lod>3.0) and the TrxR2 gene to chromosome 16 (placed 22.56 cR from D16Mit34, lod>3.0). Thus, the mouse has at least two distinct nuclear genes for TrxR that have different translocation sites in the cell. 相似文献
133.
134.
Artificial sequences of the 153 amino acids have been designed to fit the main-chain framework of the sperm whale myoglobin (Mb) structure based on a knowledge-based 3D-1D compatibility method. The previously designed artificial globin (DG1) folded into a monomeric, compact, highly helical and globular form with overall dimensions similar to those of the target structure, but it lacked structural uniqueness at the side-chain level [Isogai, Y., Ota, M., Fujisawa, T. , Izuno, H., Mukai, M., Nakamura, H., Iizuka, T., and Nishikawa, K. (1999) Biochemistry 38, 7431-7443]. In this study, we redesigned hydrophobic sites of DG1 to improve the structural specificity. Several Leu and Met residues in DG1 were replaced with beta-branched amino acids, Ile and Val, referring to the 3D profile of DG1 to produce three redesigned globins, DG2-4. These residue replacements resulted in no significant changes of their compactness and alpha-helical contents in the absence of denaturant, whereas they significantly affected the dependence of the secondary structure on the concentration of guanidine hydrochloride. The analyses of the denaturation curves revealed higher global stabilities of the designed globins than that of natural apoMb. Among DG1-4, DG3, in which 11 Leu residues of DG1 are replaced with seven Ile and four Val residues, and one Met residue is replaced with Val, displayed the lowest stability but the most cooperative folding-unfolding transition and the most dispersed NMR spectrum with the smallest line width. The present results indicate that the replacements of Leu (Met) with the beta-branched amino acids at appropriate sites reduce the freedom of side-chain conformation and improve the structural specificity at the expense of stability. 相似文献
135.
Masayuki Mori Shingo Akiyoshi Yosuke Mizuno Hisato Okuizumi Yasushi Okazaki Yoshihide Hayashizaki Masahiko Nishimura 《Mammalian genome》1998,9(9):695-709
We have applied the restriction landmark genomic scanning (RLGS) method to the SMXA recombinant inbred (RI) mouse strain
set to reveal its detailed genetic profile. A total of 663 polymorphic RLGS spot loci were identified, 576 of which were assigned
to chromosomes. Strain distribution patterns (SDPs) at 55 microsatellite marker loci were also obtained. As a result, the
total number of loci with distinct SDPs on chromosomes increased to 400. These loci were dispersed on all chromosomes, except
for the Chromosome (Chr) Y, and effectively covered the genome with an average spacing of 4 cM. The SMXA RI strain set, hereby,
would be of value for genetic study.
Received: 20 February 1998 / Accepted: 19 May 1998 相似文献
136.
Yosuke Andoh Takashi Kuramoto Norihide Yokoi Toshiro Maihara Kazuhiro Kitada Tadao Serikawa 《Mammalian genome》1998,9(4):287-293
To correlate rat genetic linkage maps with cytogenetic maps, we localized 25 new cosmid-derived simple sequence length polymorphism
(SSLP) markers and 14 existing genetic markers on cytogenetic bands of chromosomes, using fluorescence in situ hybridization
(FISH). Next, a total of 58 anchor loci, consisting of the 39 new and 19 previously reported ones, were integrated into the
genetic linkage maps. Since most of the new anchor loci were developed to be localized near the terminals of the genetic or
cytogenetic maps for each chromosome, the orientation and coverage of the whole genetic linkage maps were determined or confirmed
with respect to the cytogenetic maps. Thus, we provide here a new base for rat genetic maps.
Received: 9 September 1997 / Accepted: 11 November 1997 相似文献
137.
An electrophoretic survey was conducted for the Southeast and East Asian populations of Rana limnocharis. Results indicated that specimens from a single locality in Java derived from two genodemes showing complete allelic displacement at eight out of 25 presumptive loci examined. Within each of these genodemes, genotype frequencies at all polymorphic loci were well concordant with the Hardy-Weinberg expectation. These results strongly suggest that those specimens actually represent two biological species. Comprehensive distance analyses suggested that one of the two species from Java is genetically most divergent among all samples examined, whereas the other is most similar to the Laos sample and then to a group consisting of samples from Hongkong, western China, and the southern Ryukyus. Large values of genetic distances obtained for each combination of allopatric samples imply the presence of additional cryptic species in this nominal species. 相似文献
138.
Takaya Oguchi Masao Ota Tetsuya Ito Hideaki Hamano Norikazu Arakura Yoshihiko Katsuyama Akira Meguro Shigeyuki Kawa 《PloS one》2015,10(5)
Autoimmune pancreatitis (AIP) is a unique form of chronic pancreatitis characterized by high serum IgG4 concentration and a variety of complicating extra-pancreatic lesions. In particular, lachrymal/salivary gland lesions tend to manifest in a highly active AIP disease state, and several genes are speculated to be associated with the onset of this complication. We therefore searched for candidate susceptibility genes related to lachrymal/salivary gland lesions in a genome-wide association study (GWAS) with the GeneChip Human Mapping 500k Array Set (Affymetrix, CA) that was followed by fine mapping of additional single nucleotide polymorphisms (SNPs) in strongly significant genes with TaqMan assays. Venous blood samples were obtained from 50 type 1 AIP patients with lachrymal/salivary gland lesions (A group) and 53 type 1 AIP patients without (B group). The mean values of IgG and IG4 were both significantly different (P<0.05) between the groups. SNPs that showed a significant association with the A group at the genome-wide level (P<0.0001) were identified and subsequently used in fine SNP mapping of candidate genes. In total, five SNPs had a positive association with complicated AIP (most notably rs2284932 [P=0.0000021]) and five SNPs possessed a negative association (particularly rs9371942 [P=0.00000039]). Among them, KLF7, FRMD4B, LOC101928923, and MPPED2 were further examined for complication susceptibility using additional SNPs that were not included in the GWAS. Individual genotyping of KLF7 rs2284932 revealed that the frequency of the minor C allele was significantly increased (P=0.00062, Pc=0.0018, OR=2.98, 95%CI=1.58-5.65) in group A. The minor T allele of rs4473559 in FRMD4 demonstrated a significant association in the A group (P=0.00015, OR=3.38, 95%CI=1.77-7.65). In the LOC101928923 gene, the frequency of the minor C allele of rs4379306 was significantly decreased in group A in both TaqMan and GWAS analyses. Lastly, the minor C allele of MPPED2 rs514644 carried a significantly increased risk of complications. These four genes may be linked with the onset of lachrymal/salivary gland lesions in type 1 AIP patients and require further study. 相似文献
139.
Nobutake Yamamichi Takeshi Shimamoto Yu Takahashi Yoshiki Sakaguchi Hikaru Kakimoto Rie Matsuda Yosuke Kataoka Itaru Saito Yosuke Tsuji Seiichi Yakabi Chihiro Takeuchi Chihiro Minatsuki Keiko Niimi Itsuko Asada-Hirayama Chiemi Nakayama Satoshi Ono Shinya Kodashima Daisuke Yamaguchi Mitsuhiro Fujishiro Yutaka Yamaji Ryoichi Wada Toru Mitsushima Kazuhiko Koike 《PloS one》2015,10(4)
Background
Despite the marked increase of diverticulosis, its risk factors have not been adequately elucidated. We therefore aim to identify significantly associated factors with diverticulosis. We also aim to investigate the present state of diverticulosis in Japan.Methods
We reviewed the medical records from 1990 to 2010 that included the data of consecutive 62,503 asymptomatic colonoscopy examinees from the general population in Japan. Most recent 3,327 examinees were analyzed with 16 background factors.Results
Among the 62,503 subjects (47,325 men and 15,178 women; 52.1 ± 9.2 years old), diverticulosis was detected in 11,771 subjects (18.8%; 10,023 men and 1,748 women). The incidences of diverticulosis in 1990-2000 and 2001-2010 were respectively 13.0% (3,771 of 29,071) and 23.9% (8,000 of 33,432): the latter was much higher than the former in all age groups and for both genders. Considering the anatomical locations of colorectal diverticula, left-sided ones have markedly increased with age but not significantly changed with times. Univariate analyses of the 3,327 subjects showed significant association of diverticulosis with four basic factors (age, sex, body mass index, blood pressure), three life style-related factor (smoking, drinking, severe weight increase in adulthood), and two blood test values (triglyceride, HbA1c). The multiple logistic analysis calculating standardized coefficients (β) and odds ratio (OR) demonstrated that age (β = 0.217-0.674, OR = 1.24-1.96), male gender (β = 0.185, OR = 1.20), smoking (β = 0.142-0.200, OR = 1.15-1.22), severe weight increase in adulthood (β = 0.153, OR = 1.17), HbA1c (β = 0.136, OR = 1.15), drinking (β = 0.109, OR = 1.11), and serum triglyceride (β = 0.098, OR = 1.10) showed significantly positive association with diverticulosis whereas body mass index and blood pressure did not.Conclusions
The large-scale data of asymptomatic colonoscopy examinees from the general population from 1990 to 2010 indicated that the prevalence of diverticulosis is still increasing in Japan. Age, male gender, smoking, severe weight increase in adulthood, serum HbA1c, drinking, and serum triglyceride showed significant positive association with diverticulosis. 相似文献140.
Yosuke?Shida Kaori?Yamaguchi Mikiko?Nitta Ayana?Nakamura Machiko?Takahashi Shun-ichi?Kidokoro Kazuki?Mori Kosuke?Tashiro Satoru?Kuhara Tomohiko?Matsuzawa Katsuro?Yaoi Yasumitsu?Sakamoto Nobutada?Tanaka Yasushi?Morikawa Wataru?OgasawaraEmail author 《Biotechnology for biofuels》2015,8(1):230