Biomedical subjects

Masaru Katoh

Publications and source records attributed to Masaru Katoh.

At least 163 records · Page 9Linked to original sources

PubMed2003

Identification and characterization of human LL5A gene and mouse Ll5a gene in silico.

ARCN1, KIAA0638, TREH, DDX6, BLR1, BCL9L, UPK2, DLNB13, DLNB14, RPS25, SBDN, G6PT1, HYOU1, VPS11, HMBS, H2AFX, DPAGT1, KIAA0285, MIZF, ABCG4, NOD9, PDZK2, CBL, MCAM, RNF26, C1QTNF5, MFRP, USP2, THY1, and PVRL1 genes are located within the commonly deleted region of neuroblastoma at human chromosome 11q23.3. Here, we characterized the KIAA0638 gene within the 11q23.3 region by using bioinformatics. Because human KIAA0638 gene was homologous to human LL5B gene encoding LL5beta protein, KIAA0638 was designated LL5A gene encoding LL5alpha protein. LL5A isoform 1 (FLJ00141 type) consists of exons 1-12, 14-21 and 23, while LL5A isoform 2 (KIAA0638 type) consists of exon 1-23. LL5A isoform 1 was the major transcript among LL5A isoforms generated due to alternative splicing. Nucleotide sequence of mouse Ll5a cDNA was determined by assembling CB522359 EST and 5'-truncated mKIAA0638 cDNA. Human LL5alpha isoform 2 showed 94.4 and 35.9% total-amino-acid identity with mouse Ll5alpha and human LL5beta, respectively. LL5alpha proteins consist of Forkhead associated (FHA) domain, bipartite nuclear localization signal (NLS), Chromosome segregation ATPases (SMC) domain, and Pleckstrin homology (PH) domain. LL5alpha proteins were homologous to PtdIns(3,4,5)P3 sensor protein LL5beta in the SMC and PH domains, and were also homologous to KIF1A, KIF1B, KIF13A, KIF13B, KIF14, and SNX23 proteins in the FHA domain. LL5alpha protein might be a transducer of PtdIns(3,4,5)P3 levels to the intracellular trafficking system.

Alternative Splicing↗

PubMed2003

WNT2 and human gastrointestinal cancer (review).

WNT2 gene on human chromosome 7q31 is a paralog of the WNT2B gene on human chromosome 1p13. Rat Wnt2 gene was identified within rat genome draft sequence AC095247.4. Human WNT2 showed 96.4% total-amino-acid identity with rat Wnt2, 96.1% with mouse Wnt2, 68.6% with zebrafish wnt2, and 67.8% with fugu wnt2. WNT2 is an evolutionarily conserved secreted-type glycoprotein belonging to the WNT family. WNT2 mRNA is expressed in human fetal lung and placenta, but almost undetectable in normal gastrointestinal tract. WNT2 mRNA is frequently up-regulated in human gastric cancer due to tumor-stromal interaction, and WNT2 gene is rarely amplified in human gastric cancer. WNT2 mRNA is also frequently up-regulated in colorectal polyps, primary colorectal cancer of stage A-C, and also in liver metastasis from colorectal cancer. Putative biding sites for estrogen receptor, GATA-1, AP-2, TCF-1, BHLH, MBF-I, p53, and HNF-5 are located within the 5'-flanking region of human WNT2 gene. WNT2 is up-regulated by beta-estradiol in human MCF-7 cells; however, the mechanism of WNT2 up-regulation in most cases of gastrointestinal cancer remains to be elucidated. WNT2 is a tumor marker of gastric and colorectal cancer. Detection of theWNT2 protein in feces by immunohistochemistry or ELISA and WNT2 mRNA in feces by cDNA-PCR or custom-made microarray could be applied for screening of colorectal cancer. Because WNT2 up-regulation leads to carcinogenesis through activation of the WNT-beta-catenin pathway, WNT2 specific antagonist might be applied for chemoprevention or treatment of gastrointestinal cancer. WNT2 gene is one of the targets for pharmacogenomics in the field of oncology.

Animals↗

PubMed2003

Identification and characterization of TRIP8 gene in silico.

TRIP1-TRIP15 genes encode thyroid hormone receptor beta (TR beta)-binding proteins. TRIP10 gene encodes FNBP1 family protein with FCH, FBH, and SH3 domains. Among 15 TRIP genes, TRIP8 gene remained uncharacterized except TRIP8 partial cDNA (L40411). Here, we determined the complete coding sequence of TRIP8 gene by using bio-informatics. Nucleotide sequence of full-length TRIP8 cDNA was determined in silico by assembling nucleotide sequences of FLJ14374 and DKFZp761F0118 cDNAs. TRIP8 protein (2540 aa) was found to consist of two bipartite nuclear localization signals (codon 352-368 and 2365-2381), TRI8H1 domain (codon 1697-1873), TRI8H2 domain (codon 2057-2351), and JMJC domain (codon 2387-2486). TRI8H1, TRI8H2 and JMJC domains were conserved among TRIP8, 5qNCA (C5orf7) and TSGA proteins. TR beta-binding domain was overlapped with N-terminal part of TRI8H2 domain, and C2HC4-type zinc finger-like motif was located within C-terminal part of TRI8H1 domain. Because JMJC domain proteins are implicated in chromatin remodeling, TRIP8 was predicted to be a transcriptional regulator associated with nuclear hormone receptors. Human TRIP8 gene, consisting of 26 exons, was about 300 kb in size. Intra-species comparative genomics revealed that TRIP8-EGR2 locus at human chromosome 10q21.3 and 5qNCA-EGR1 locus at human chromosome 5q31 are paralogous regions within human genome. Microsatellite marker D10S1225, associated with Alzheimer's disease, non-syndromic congenital retinal non-attachment (NCRNA) and non-syndromic autosomal recessive persistent hyperplastic primary vitreous (arPHPV), was located within the TRIP8-EGR2 locus. This is the first report on comprehensive characterization of the TRIP8 gene.

ATPases Associated with Diverse Cellular Activitie↗

PubMed2003

Identification and characterization of human PPFIA4 gene in silico.

Human PPFIA1 (also known as LIP.1 or Liprin alpha1) gene, located within CCND1-FGF4-EMS1 amplicon at human chromosome 11q13.3, encodes KIF1A-binding protein, which is implicated in trafficking of LAR subfamily PTPases and AMPA-type glutamate receptors. Human PPFIA4 (AF034801) and rat Ppfia4 (AY057064) are 5'-truncated partial cDNAs, and the complete coding sequence of PPFIA4 ortholog of any species remained to be identified. Here, we determined the complete coding sequence of human PPFIA4 gene by using bioinformatics. Exons 1-12 of PPFIA4 gene were located within human genome sequence AC096632.3, while exons 11-29 within AL451082.6. PPFIA4-MYOG locus (human chromosome 1q32.1) was paralogous to PPFIA2-LIN7A-MYF5-MYF6 locus (12q21.31), which was also paralogous to PPFIA3-LIN7B locus (19q13.41). PPFIA4 (1186 aa) showed 70.9%, 67.1%, and 61.8% total-amino-acid identity with PPFIA2, PPFIA1, and PPFIA3, respectively. PPFIA family members consist of PFIH1, PFIH2, PFIH3, PFIH4 domains and three SAM (Sterile alpha motif) domains. C-terminal binding domain for GRIP proteins (VRTYSC motif) was present in PPFIA1, PPFIA2 and PPFIA3, but not in PPFIA4. Bipartite nuclear localization signal was included within PFIH4 domain. PFIH2 domain was identical to ERM or Smc domain. The region spanning PFIH2-PFIH3 domains is the binding domain for KIF1A. The region spanning SAM1-SAM3 domains is the binding domain for LAR subfamily PTPases and PPFIBP (Liprin beta) family proteins. This is the first report on comprehensive characterization of PPFIA4 belonging to the PPFIA family of kinesin-cargo linkers.

Adaptor Proteins, Signal Transducing↗

PubMed2003

Identification and characterization of human GRID2IP gene and rat Grid2ip gene in silico.

Formin-homology proteins are implicated in the cell polarity control through the assembly of specific actin structures. FMNL1/KW-13/FMNL, FMNL2/KIAA1902/FHOD2, FMNL3/KIAA2014, DAAM1, DAAM2, DIAPH1 and DIAPH2 are Formin-homology proteins with the FDD domain, while Fmn1, Fmn2, FHOD1 and Grid2ip/Delphilin are Formin-homology proteins without the FDD domain. Mouse Grid2ip links glutamate receptor delta2 subunit with actin cytoskeleton and various signaling molecules. Here, we identified and characterized human GRID2IP gene as well as rat Grid2ip gene by using bioinformatics. Human GRID2IP gene was identified within human genome sequence CTD-2195F21 (AC072052.6). Human GRID2IP gene, consisting of 21 exons, was mapped to human chromosome 7p22.1. Rat Grid2ip gene, consisting of 21 exons, was identified within rat genome sequence CH230-82F18 (AC126572.3). Human GRID2IP (1020 aa) showed 91.7% total-amino-acid identity with rat Grid2ip (1024 aa), and 92.7% total-amino-acid identity with mouse Grid2ip. Human GRID2IP protein was found to consist of PDZ domain (codon 94-166), GRCAH domain (codon 204-269), FH1 domain (codon 559-621), and FH2 domain (codon 640-1005). GRCAH domain identified in this study was conserved among mammalian GRID2IP orthologs and mammalian CIP98/KIAA1526 orthologs. This is the first report on comprehensive characterization of human GRID2IP gene as well as on identification of GRCAH domain.

Amino Acid Sequence↗

PubMed2002

Induction of homologue of Slimb ubiquitin ligase receptor by mitogen signaling.

Homologue of Slimb (HOS) is the substrate-recognizing component of the SCF(HOS)-Roc1 E3 ubiquitin protein ligase. This ligase mediates ubiquitination of the inhibitor of NF-kappaB transcription factor (IkappaB). We have found that HOS is highly expressed in a number of human cancer cell lines. The rates of the HOS gene transcription as well as HOS mRNA and protein levels were up-regulated in cells treated with mitogens or transfected with the inducers of mitogen-activated protein kinase pathway. Conversely, mitogen withdrawal strikingly reduced HOS levels during differentiation of mouse myoblasts. Activators of mitogen-activated protein kinase accelerated IkappaBalpha degradation and increased NF-kappaB transcriptional activity. Inhibition of HOS function via expression of dominant negative HOS (HOS(DeltaF)) initiated mouse myoblast differentiation and prevented Ras-mediated acceleration of IkappaBalpha degradation as well as NF-kappaB trans-activation and transformation of NIH3T3 cells. These data link the induction of HOS in proliferating cells with mitogen-signaling-dependent inhibition of cell differentiation and promotion of cell transformation.

3T3 Cells↗

PubMed2002

Inhibition of HOS expression and activities by Wnt pathway.

BetaTrCP and HOS are closely related F-box proteins, which play key roles in ubiquitination and degradation of beta-catenin and IkappaB through associating with those phosphorylated substrates and recruiting SCF E3 ubiquitin ligase. Here we report that activation of Wnt/beta-catenin signal transduction pathway elevates betaTrCP levels but inhibits expression of HOS in 293T cells. Similar disparity is likely to exist in human colorectal tumors. In the NIH3T3 cells, which express HOS, but not betaTrCP, Wnt/beta-catenin signaling leads to inhibition of HOS promoter activity and NF-kappaB-driven transcription as well as to stabilization of beta-catenin. These results indicate that expression and activities of HOS are negatively regulated by Wnt/beta-catenin pathway.

3T3 Cells↗

PubMed2002

Up-regulation of Frizzled-10 (FZD10) by beta-estradiol in MCF-7 cells and by retinoic acid in NT2 cells.

Frizzled (FZD) genes encode receptors for WNTs, which play key roles in carcinogenesis and embryogenesis. We have previously cloned the FZD10 gene, and demonstrated up-regulation of FZD10 mRNA in the cervical cancer cell line HeLa S3, gastric cancer cell lines TMK1 and MKN74, and 4 cases out of 10 cases of primary gastric cancer. Here, effects of beta-estradiol, retinoic acid, and inflammatory cytokines on expression of FZD10 mRNA in human cancer cell lines were investigated. FZD10 mRNA was undetectable in MCF-7 cells derived from breast cancer, and was significantly up-regulated by beta-estradiol in MCF-7 cells with a peak at 24 h after treatment. FZD10 mRNA was expressed in NT2 cells, which are reported to differentiate into neuronal cells after exposure to retinoic acid. Although expression level of FZD10 mRNA was unchanged until 36 h after retinoic-acid treatment, FZD10 mRNA was up-regulated at 48 and 72 h after retinoic-acid treatment in NT2 cells. Effects of inflammatory cytokines on FZD10 mRNA expression in a gastric cancer cell line MKN45 was next investigated. FZD10 mRNA was undetectable in MKN45 cells, and was not up-regulated by IFNgamma and TNFalpha in MKN45 cells. Because we have previously demonstrated up-regulation of WNT2 mRNA by beta-estradiol in MCF-7 cells, FZD10 and WNT2 mRNAs were found to be up-regulated together by beta-estradiol in MCF-7 cells with the same time course. Synchronous up-regulation of FZD10 and WNT2 mRNAs might lead to activation of the WNT signaling pathway in human breast cancer.

Antineoplastic Agents↗

PubMed2002

Frizzled-10, up-regulated in primary colorectal cancer, is a positive regulator of the WNT - beta-catenin - TCF signaling pathway.

WNT signaling pathway is implicated in embryogenesis as well as in carcinogenesis. We have previously cloned and characterized Frizzled-1 (FZD1), FZD2, FZD3, FZD4, FZD5, FZD6, FZD7, FZD8, and FZD10, encoding seven-transmembrane-type WNT receptors. Here, expression of FZD10 mRNA in various types of human cancer and effects of FZD10 mRNA microinjection into Xenopus early embryos were investigated. Northern blot analyses revealed relatively high-level expression of 4.0-kb FZD10 mRNA in cervical cancer cell lines HeLa S3, SKG-I, SKG-IIIa, and in a glioblastoma cell line A-172. Matched tumor/normal expression array analysis revealed significant up-regulation of FZD10 mRNA in 2 cases of primary colon cancer. Function of FZD10 was next investigated by using Xenopus axis duplication assay, in which positive regulators of the WNT - beta-catenin - TCF signaling pathway induce axis duplication. Injection of wild-type FZD10 mRNA into the ventral marginal zone of 4-cell-stage Xenopus embryos induced partial axis duplication in 40% of embryos. Ventral injection of Thr579Ala FZD10 mRNA or Val581Leu FZD10 mRNA with mutations in the C-terminal Ser/Thr-X-Val motif also induced partial axis duplication in about 40% of embryos. Furthermore, ventral injection of FZD10 mRNA significantly augmented the potential of co-injected Xenopus wnt-8 (Xwnt-8) mRNA to induce complete axis duplication. These results suggest that up-regulation of FZD10 mRNA in several types of human cells might lead to carcinogenesis through activation of the beta-catenin - TCF signaling pathway synergistically with some class of WNTs.

Animals↗

PubMed2002

Molecular cloning and characterization of mouse Wnt14b, clustered with mouse Wnt3 in mouse chromosome 11.

WNTs are a family of secreted-type glycoproteins implicated in embryogenesis and carcinogenesis. We have previously cloned and characterized human WNT2B/WNT13, WNT3, WNT3A, WNT5B, WNT6, WNT7B, WNT8A, WNT8B, WNT10A, WNT10B, WNT11, WNT14, and WNT14B/WNT15. WNT14B gene is clustered with WNT3 gene in human chromosome 17q21, and mRNA expression of WNT14B is significantly up-regulated by retinoic acid during the early phase of neuronal differentiation in human NT2 cells. Here, we identified mouse Wnt14b gene fragments in mouse genome draft sequence AL596108.5 by using bioinformatics, and isolated mouse Wnt14b cDNAs by using cDNA-PCR. Mouse Wnt14b was found to encode a 359-amino-acid WNT family protein with the N-terminal signal peptide, an N-linked glycosylation site, and 24 conserved cysteine residues. Mouse Wnt14b showed 92.5% total-amino-acid identity with human WNT14B, and 64.2% total-amino-acid identity with human WNT14. Mouse Wnt14b gene, consisting of 4 exons, was clustered with mouse Wnt3 gene in mouse chromosome 11. Mouse Wnt14b mRNA was relatively highly expressed in 17-day embryo, and also expressed in adult brain, kidney, liver, 7-day embryo, and 11-day embryo. This is the first report on molecular cloning and characterization of mouse Wnt14b.

Amino Acid Sequence↗

PubMed2002

Molecular cloning and characterization of human SOX17.

SOX proteins are a family of transcription factors with high-mobility-group DNA-binding domain (HMG box) homologous to SRY, which are implicated in embryogenesis. Xenopus Sox17 alpha, Sox17 beta, and Sox3 are reported to negatively modulate the WNT - beta-catenin - TCF signaling pathway. Here, human SOX17 gene fragments were identified in human genome draft sequences by using bioinformatics, and SOX17 cDNAs were isolated by using cDNA-PCR. Human SOX17 was found to encode a 414-amino-acid protein with a HMG box, which was homologous to SOX18 and SOX7. SOX17 gene, consisting of 2 exons, was located in human chromosome 8q12-q13 region. SOX17 mRNAs of 2.5- and 2.2-kb in size were detected in adult heart, lung, spleen, testis, ovary, placenta, fetal lung, and kidney. In normal gastrointestinal tract, SOX17 mRNA was preferentially expressed in esophagus, stomach and small intestine than in colon and rectum. SOX17 mRNA was almost undetectable in human cancer cell lines HL-60, HeLa S3, K-562, MOLT-4, Raji, SW480, A549, G-361, and also in 66 cases of human primary tumors derived from various tissues, except one case of primary cervical cancer. This is the first report on molecular cloning and characterization of human SOX17.

Amino Acid Sequence↗

PubMed2002

Up-regulation of WNT8B mRNA in human gastric cancer.

WNT - beta-catenin - TCF signaling pathway is activated by Xenopus wnt-8 (Xwnt-8) during Xenopus early development, and dysregulated activation of beta-catenin - TCF signaling pathway in mammalian cells leads to carcinogenesis. We have previously cloned and characterized human WNT8A, one of human orthologues of Xwnt-8. Here, we cloned and characterized human WNT8B by using bioinformatics, cDNA-PCR, and RACE. WNT8B gene of about 23-kb in size consisted of six exons, and encoded a 351-amino-acid polypeptide with the N-terminal signal peptide and two N-linked glycosylation sites. C-terminal region of WNT8B, WNT8A, WNT2, and WNT2B were longer than that of other human WNTs. Thirty-five nucleotide changes between WNT8B isolated by us and WNT8B isolated by another group resulted in Gly230Ala and Arg284Leu amino-acid substitutions. Gly230 and Arg284 of WNT8B were conserved in WNT8A. Gly230-Arg284 WNT8B allele was also identified in human genome draft sequences AL133352.10, AL359759.18, and human EST BF732616. These results indicate that the Gly230-Arg284 WNT8B cDNA isolated in this study is derived from the more common WNT8B allele. WNT8B mRNAs of 4.4- and 3.5-kb in size were weakly detected in a colorectal cancer cell line SW480, but were undetectable in any normal human tissues by using Northern blot analyses. WNT8B was significantly up-regulated in gastric cancer cell lines KATO-III (signet-ring cell carcinoma) and MKN45 (poorly differentiated adenocarcinoma), and also in 5 out of 10 cases of primary gastric cancer. WNT8B might play key roles in gastric cancer through activation of the beta-catenin - TCF signaling pathway.

Alleles↗

PubMed2002

Regulation of WNT3 and WNT3A mRNAs in human cancer cell lines NT2, MCF-7, and MKN45.

We have previously cloned and characterized human WNT2B/WNT13, WNT3, WNT3A, WNT5B, WNT6, WNT7B, WNT8A, WNT10A, WNT10B, WNT11, WNT14, and WNT14B/WNT15 by using bioinformatics, cDNA-library screening, cDNA-PCR, and RACE. WNT3 and WNT3A genes are two human paralogues of mouse proto-oncogene Wnt3, which induces carcinogenesis through activation of the beta-catenin - TCF signaling pathway. Here, regulation of WNT3 and WNT3A mRNAs in human cancer cell lines was investigated. WNT3 and WNT3A mRNAs were co-expressed in an embryonal carcinoma cell line NT2, which is reported to differentiate into postmitotic CNS neurons by treatment with retinoic acid for two weeks. Expression level of WNT3 mRNA in NT2 cells was not changed during 72 h after retinoic acid treatment, while expression of WNT3A mRNA was down-regulated in NT2 cells by retinoic acid. WNT3 and WNT3A mRNAs were also co-expressed in a breast cancer cell line MCF-7, and were down-regulated together by beta-estradiol in MCF-7 cells. Expression of WNT3 mRNA in a gastric cancer cell line MKN45 was not changed after treatment with tumor necrosis factor alpha (TNFalpha) or interferon gamma (IFNgamma), and that of WNT3A mRNA was undetectable before and after treatment with TNFalpha or IFNgamma. WNT3A, down-regulated by retinoic acid in NT2 cells, might play key roles in the maintenance of NT2 cells in the undifferentiated proliferation stage through activation of the beta-catenin - TCF signaling pathway.

Down-Regulation↗

PubMed2002

Molecular cloning and characterization of human GIPC2, a novel gene homologous to human GIPC1 and Xenopus Kermit.

PDZ-domain protein GIPC1/GIPC interacts with GTPase-activating protein RGS-GAIP, TGFbeta type III receptor, and integrin alpha6A subunit. Kermit, a Xenopus orthologue of human GIPC1, interacts with some class of WNT receptor. In this study, we identified a novel GIPC1-related gene in human genome by using bioinformatics, and isolated GIPC2 cDNAs by using cDNA-PCR. GIPC2 encoded a 315-amino-acid protein with a central PDZ domain, which showed 62.0% total-amino-acid identity with GIPC1. Both GIPC2 gene on human chromosome 1 and GIPC1 gene on human chromosome 19p13.1 were found to consist of 6 exons. Exon-intron structures of GIPC2 gene and GIPC1 gene were well conserved. GIPC2 mRNA was relatively highly expressed in ascending colon, followed by kidney and pancreas. Among 3.7-, 2.6-, and 1.7-kb GIPC2 mRNAs generated due to alternative polyadenylation, 2.6-kb GIPC2 mRNA was the major GIPC2 transcript in adult kidney. Expression of GIPC2 mRNA was significantly down-regulated in 6 out of 14 cases of primary kidney tumors, in 5 out of 11 cases of primary colon tumors, and in 1 out of 7 cases of primary rectal tumors. Because GIPC2 might bind to TGFbeta type III receptor or some class of WNT receptor, just like GIPC1 or Kermit, down-regulation of GIPC2 mRNA in human primary tumors might lead to interference of TGFbeta signaling or some class of WNT signaling. This is the first report on molecular cloning of GIPC2, the second member of the GIPC gene family, which is down-regulated in human primary kidney and colorectal tumors.

Adaptor Proteins, Signal Transducing↗

PubMed2002

Molecular cloning and characterization of human GIPC3, a novel gene homologous to human GIPC1 and GIPC2.

Kermit is a Xenopus orthologue of human GIPC1/GIPC, which interacts with Frizzled-3 (FZD3) class of WNT receptor to modulate WNT signaling. GIPC1 interacts with TGFbeta type III receptor to enhance TGFbeta signaling. We have recently cloned and characterized a novel GIPC1-related gene, GIPC2. During isolation of GIPC2, we identified another novel GIPC1-related gene, GIPC3, by using bioinformatics. In this study, we isolated GIPC3 cDNAs from poly(A)+ RNA of human fetal lung. GIPC3 encoded a 312-amino-acid protein with a central PDZ domain, which showed 59.9% total-amino-acid identity with GIPC1, 55.3% total-amino-acid identity with GIPC2, and 57.2% total-amino-acid identity with Xenopus Kermit. GIPC3 gene on human chromosome 19p13.3 was found to consist of 6 exons, just like GIPC1 gene and GIPC2 gene. The 4.5-kb GIPC3 mRNA was almost ubiquitously expressed in normal adult tissues as well as in normal fetal tissues. Expression level of GIPC3 mRNA was relatively higher in jejunum, followed by lymph node, parietal lobe in brain, fetal spleen, and fetal thymus. GIPC3 mRNA was expressed in cervical cancer cell line HeLa S3, chronic myelogenous leukemia cell line K-562, and melanoma cell line G-361. GIPC3 mRNA was also expressed in gastric cancer cell lines TMK1 and MKN7; however, expression level of GIPC3 mRNA in TMK1 and MKN7 cells were significantly lower than that in normal stomach. This is the first report on molecular cloning of GIPC3, the third member of the GIPC gene family.

Adaptor Proteins, Signal Transducing↗

PubMed2002

Molecular cloning and expression of mouse Wnt14, and structural comparison between mouse Wnt14-Wnt3a gene cluster and human WNT14-WNT3A gene cluster.

Glycoprotein WNTs play key roles in carcinogenesis and embryogenesis. Human WNT14 and WNT3A genes are clustered in human chromosome 1q42 region with an interval of about 58 kb. Here, mouse Wnt14 was isolated to compare the structure of human WNT14-WNT3A gene cluster with that of mouse Wnt14-Wnt3a gene cluster. Mouse Wnt14 showed 98.1% total-amino-acid identity with human WNT14, and 61.9% total-amino-acid identity with human WNT14B/WNT15. Mouse Wnt14 mRNA was expressed in adult brain, lung, skeletal muscle, heart, and 17-day embryo. Mouse Wnt14 and Wnt3a genes were clustered in head-to-head manner with an interval of about 16 kb. Exon-intron structures were well conserved between human WNT14-WNT3A gene cluster and mouse Wnt14-Wnt3a gene cluster. Capicua-related sequence and AK024248-related sequence were identified in the intergenic region of human Wnt14-Wnt3a gene cluster as well as in other human chromosomal loci, but not in that of mouse Wnt14-Wnt3a gene cluster. Capicua-related sequences were pseudogenes derived from Capicua gene on human chromosome 19q13. Capicua pseudogene and AK024248-related sequence were clustered in tail-to-tail manner with interval ranging from 2.2 to 11.0 kb. AK024248-related sequences in several human genome draft sequences were truncated in the 3'-portion compared with that in the intergenic region of human WNT14-WNT3A gene cluster. This is the first report on structural comparison of WNT gene clusters in human genome and in mouse genome.

Amino Acid Sequence↗

PubMed2002

Molecular cloning and characterization of mouse Gipc3.

GIPC1/GIPC interacts with GTPase-activating protein RGS-GAIP, transmembrane protein M-SemF, receptor tyrosine kinase TrkA, integrin alpha 6A subunit, and TGF beta type III receptor. Kermit, a Xenopus orthologue of human GIPC1, interacts with Frizzled-3 (FZD3) class of WNT receptor. We have recently cloned and characterized human GIPC2 and GIPC3. Here, we identified mouse Gipc3 gene fragments by using bioinformatics, and isolated mouse Gipc3 cDNAs by using cDNA-PCR. Mouse Gipc3 gene encoded a 297-amino-acid protein, showing 86.2% total-amino-acid identity with human GIPC3. In addition to the central PDZ domain, GIPC homologous domain 1 (GH1 domain) and GH2 domain were found to be conserved among mouse Gipc3, Gipc1, Gipc2, and Xenopus Kermit. Mouse Gipc3 gene was found to consist of 6 exons, and exon-intron structure was well conserved between mouse Gipc3 gene and human GIPC3 gene. Mouse Gipc3 mRNA was relatively highly expressed in adult lung, and was also expressed in brain and testis, but was almost undetectable in 7-, 11-, 15, and 17-day whole embryos. This is the first report on molecular cloning and initial characterization of mouse Gipc3.

Adaptor Proteins, Signal Transducing↗

PubMed2002

Expression of human SOX7 in normal tissues and tumors.

SOX transcription factors with high-mobility-group DNA-binding domain (HMG box) play key roles in embryogenesis. Some members of the SOX family are negative regulators of the WNT-beta-catenin-TCF signaling pathway. We have previously cloned and characterized human SOX17, constituting a subfamily with SOX7 and SOX18. Another group mapped SOX7 gene to human chromosome 8p22, and reported almost ubiquitous expression of 5.0-kb SOX7 mRNA in human normal tissues. Here, expression of SOX7 mRNA was investigated by using SOX7 specific probe, which hybridized to 3.8-kb human SOX7 mRNA, but not to 5.0-kb mRNA. SOX7 mRNA was relatively highly expressed in adult lung, trachea, lymph node, placenta, fetal lung, and heart. In adult heart, SOX7 mRNA was more highly expressed in ventricules, inter-ventricular septum and apex than in atriums. SOX7 mRNA was significantly up-regulated in pancreatic cancer cell lines BxPC-3, PSN-1, Hs766T, and in 4 cases out of 8 cases of primary gastric cancer. SOX7 mRNA was relatively highly expressed in a gastric cancer cell line MKN45, esophageal cancer cell lines TE2, TE3, TE4, TE5, TE7, TE8, TE11, TE12, and TE13. On the other hand, SOX7 mRNA was significantly down-regulated in 7 out of 18 cases of primary colorectal tumors, in 4 out of 9 cases of primary breast cancer, in 4 out of 14 cases of primary kidney tumors, and also in some cases of primary lung and prostate cancer. SOX7 gene might be one of cancer-associated genes on human chromosome 8p22.

DNA-Binding Proteins↗