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Genes Other (gene + other)
Selected AbstractsThe whorl-specific action of a petunia class B floral homeotic geneGENES TO CELLS, Issue 2 2000Suguru Tsuchimoto Background GREEN PETAL (GP) is thought to be a petunia class B floral homeotic gene, because the gp mutant flower displays a severe homeotic conversion of petals into sepals in the second whorl. However, since the third whorl stamens remain unaffected in the gp null mutant, gp is different from class B mutants in Arabidopsis and Antirrhinum, which also show a conversion of the third whorl stamens into the carpelloid tissue. BLIND (BL) is thought to be a petunia class A floral homeotic gene, because the bl mutant flower displays homeotic conversions of sepals into the stigmatoid tissue in the first whorl and of the corolla limb into antheroid structures in the second whorl. Results A double mutant line homozygous for both bl and gp mutations was constructed. The bl gp double mutant flower displays homeotic conversions of sepals into the stigmatoid tissue in the first whorl and of the corolla limb into antheroid structures with stigmatoid tips in the second whorl. In the third and fourth whorls of the mutant flower, organs remained unchanged. In the gp flower, a petunia B-type gene FBP1 is expressed strongly in the third whorl organs, but much more weakly in the second whorl organs. In the bl gp flower, FBP1 was found to be expressed strongly in the second whorl organs as well as in the third whorl organs. Conclusions Petunia has a class B gene other than GP that determines organ identities, both in the second and third whorls of the double mutant flower, and the action of the postulated class B gene (here called PhBX) is prevented by the BL gene in the second whorl of the gp flower. PhBX appears to be a gene that specifically interacts with the FBP1 gene, and is involved in the up-regulation of FBP1. [source] Isolation, Characterization and Preliminary Genetic Analysis of Laboratory Tricyclazole-resistant Mutants of the Rice Blast Fungus, Magnaporthe griseaJOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2006C. Q. Zhang Abstract The minimum inhibitory concentration of tricyclazole for hyphal melanization (MIC-H) was adopted to detect the sensitivity of 129 Magnaporthe grisea isolates collected in China in 2000. Results showed that the mean MIC-H was 0.2 ,g/ml and no isolate with a MIC-H ,1 ,g/ml was detected. Therefore, 1 ,g/ml was chosen as a discriminatory dose to identify resistant mutants generated by ultraviolet (UV) radiation. Only three low-level resistant (R) mutants derived from the sensitive (S) isolate TH16 were obtained. In addition, fitness decrease was observed for all mutants, with lower sporulation ability and pathogenicity to rice than that of the wild strain TH16. Four crosses between S × R and S × S were tested to determine the inheritance mode of resistance during the process of sexual recombination by analysing the sensitivity of hybrid F1 progeny to tricyclazole. Progeny of crosses between a tricyclazole-sensitive strain and tricyclazole-resistant mutants segregated in a 1 : 1 (R : S) ratio and no segregation was found in the cross of S × S, indicating that each mutant contained a single gene for resistance. No nucleotide differences leading to amino acid changes in the coding sequences for 1,3,6,8-tetrahydroxynaphthalene reductase (4HNR) and 1,3,8-trihydroxynaphthalene reductase (3HNR) were found between resistant mutants and sensitive strains. Therefore, it is preliminarily concluded that tricyclazole resistance in M. grisea was conferred by a one-locus mutation in a single Mendelian gene other than those encoding for 4HNR or 3HNR. [source] Genetics of dermatofibrosarcoma protuberans family of tumors: From ring chromosomes to tyrosine kinase inhibitor treatmentGENES, CHROMOSOMES AND CANCER, Issue 1 2003Nicolas Sirvent Dermatofibrosarcoma protuberans (DP) is a rare, slow-growing, infiltrating dermal neoplasm of intermediate malignancy, made up of spindle-shaped tumor cells often positive for CD34. The preferred treatment is wide surgical excision with pathologically negative margins. At the cytogenetic level, DP cells are characterized by either supernumerary ring chromosomes, which have been shown by using fluorescence in situ hybridization techniques to be derived from chromosome 22 and to contain low-level amplified sequences from 17q22-qter and 22q10,q13.1, or t(17;22), that are most often unbalanced. Both the rings and linear der(22) contain a specific fusion of COL1A1 with PDGFB. Similar to other tumors, the COL1A1-PDGFB fusion is occasionally cryptic, associated with complex chromosomal rearrangements. Although rings have been mainly observed in adults, translocations have been reported in all pediatric cases. DP is therefore a unique example of a tumor in which (i) the same molecular event occurs either on rings or linear translocation derivatives, (ii) the chromosomal abnormalities display an age-related pattern, and (iii) the presence of the specific fusion gene is associated with the gain of chromosomal segments, probably taking advantage of gene dosage effects. In all DP cases that underwent molecular investigations, the breakpoint localization in PDGFB was found to be remarkably constant, placing exon 2 under the control of the COL1A1 promoter. In contrast, the COL1A1 breakpoint was found to be variably located within the exons of the ,-helical coding region (exons 6,49). No preferential COL1A1 breakpoint and no correlation between the breakpoint location and the age of the patient or any clinical or histological particularity have been described. The COL1A1-PDGFB fusion is detectable by multiplex RT-PCR with a combination of forward primers designed from a variety of COL1A1 exons and one reverse primer from PDGFB exon 2. Recent studies have determined the molecular identity of "classical" DP, giant cell fibroblastoma, Bednar tumor, adult superficial fibrosarcoma, and the granular cell variant of DP. In approximately 8% of DP cases, the COL1A1-PDGFB fusion is not found, suggesting that genes other than COL1A1 or PDGFB might be involved in a subset of cases. It has been proposed that PDGFB acts as a mitogen in DP cells by autocrine stimulation of the PDGF receptor. It is encouraging that inhibitory effects of the PDGF receptor tyrosine kinase antagonist imatinib mesylate have been demonstrated in vivo; such targeted therapies might be warranted in the near future for treatment of the few DP cases not manageable by surgery. © 2003 Wiley-Liss, Inc. [source] Differential involvement of the hypermethylator phenotype in hereditary and sporadic colorectal cancers with high-frequency microsatellite instabilityGENES, CHROMOSOMES AND CANCER, Issue 3 2002Hiroyuki Yamamoto High-frequency microsatellite instability (MSI-H) due to defective DNA mismatch repair occurs in the majority of hereditary nonpolyposis colorectal cancers (HNPCCs) and in a subset of sporadic malignant tumors. Clinicopathologic and genotypic features of MSI-H colorectal tumors in HNPCC patients and those in sporadic cases are very similar but not identical. Correlation between the MSI phenotype and aberrant DNA methylation has been highlighted recently. A strong association between MSI and CpG island methylation has been well characterized in sporadic colorectal cancers with MSI-H but not in those of hereditary origin. To address the issue, we analyzed hereditary and sporadic colorectal cancers for aberrant DNA methylation of target genes using methylation-specific polymerase chain reaction. DNA methylation of the MLH1, CDKN2A, MGMT, THBS1, RARB, APC, and p14ARF genes was found in 0%, 23%, 10%, 3%, 73%, 53%, and 33% of 30 MSI-H cancers in HNPCC patients and in 80%, 55%, 23%, 23%, 58%, 35%, and 50% of 40 sporadic colorectal cancers with MSI-H, respectively. Cases showing methylation at three or more loci of six genes other than MLH1 were defined as CpG island methylator phenotype,positive (CIMP+), and 23% of HNPCC tumors and 53% of sporadic cancers with MSI-H were CIMP+ (P = 0.018). Differences in the extent of CpG island methylation, coupled with the differential involvement of several genes by methylation, in HNPCC tumors and sporadic MSI-H colorectal cancers may be associated with diverging developmental pathways in hereditary and sporadic cancers despite similar MSI-H phenotypes. © 2002 Wiley-Liss, Inc. [source] High-resolution mapping of the Gli3 deletion in the mouse extra-toesH mutantGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 3 2007Matthieu Genestine Abstract Extra-toes is a semidominant mutation that affects the Gli3 gene and provokes limb and brain abnormalities. Among the different alleles of this mutation, XtH is due to a deletion that has not yet been fully characterized. Using a PCR-based strategy, we undertook a high-resolution mapping of this deletion and confirmed that XtH is a null allele of Gli3. We further designed a PCR test to identify unequivocally heterozygous and homozygous embryos from their wild-type littermates. Despite the length of the XtH deletion, available data on the mouse genome indicate that no genes other than Gli3 are deleted in XtH mutants. Thus, the XtH mutation can be used as a model for studying the effects that absence of Gli3 function has during development. genesis 45:107,112, 2007. © 2007 Wiley-Liss, Inc. [source] Genetic background of Japanese patients with adult-onset storage diseases in the liverHEPATOLOGY RESEARCH, Issue 10 2007Hisao Hayashi In contrast to primary lysosomal diseases in young subjects, adult-onset liver storage disorders may be explained by non-lysosomal genetic defects. The aim of the present review is to summarize the genetic backgrounds of Japanese patients with hemochromatosis of unknown etiology, Wilson disease of primary copper toxicosis, and the black liver of Dubin,Johnson syndrome. Three patients with middle-age onset hemochromatosis were homozygous for mutations of HJV and two patients were homozygous for mutations of TFR2. Minor genes other than HJV and TFR2 might be involved in Japanese patients. Five of the six patients with Wilson disease were compound heterozygous, while the remaining patient was heterozygous for the mutation in ATP7B responsible for copper toxicosis. Involvement of MURR1 was not proved in the heterozygote of ATP7B. Because of ferroxidase deficiency,most patients had secondary lysosomes shared by cuprothioneins and iron complex. Six patients with Dubin,Johnson syndrome were homozygous or compound heterozygous for mutant MRP2. Despite complex metabolic disorders, the syndrome had a single genetic background. Thus, most patients with adult-onset lysosomal proliferation in the liver had genetic defects in non-lysosomal organelles, named the secondary lysosomal diseases. The proliferating lysosomes in these conditions seemed to be heterogeneous in their matrices. [source] Asthma and atopy are associated with chromosome 17q21 markers in Chinese childrenALLERGY, Issue 4 2009T. F. Leung Background:, Single-nucleotide polymorphism (SNP)-based genome-wide association study revealed that markers on chromosome 17q21 were linked to childhood asthma but not atopy in Caucasians, with the strongest signal being detected for the SNP rs7216389 in the ORMDL3 gene. Such association was unknown in Chinese. This study delineated the allele and genotype frequencies of 10 SNPs at chromosome 17q21, and investigated the relationship between these SNPs and asthma and plasma IgE in southern Chinese children. Methods:, Asthmatic children and non-allergic controls were recruited from pediatric clinics. Their plasma total and aeroallergen-specific IgE concentrations were measured by immunoassay. Ten SNPs on 17q21 region were genotyped by multiplex SNaPshotÔ, and their genotype associations with asthma traits analyzed using multivariate regression. Results:, 315 patients and 192 controls were enrolled. The allele frequency for C allele of rs7216389 varied significantly from 0.232 in our controls, 0.389 in Han Chinese to 0.536 in Caucasians. Asthma diagnosis was associated with rs11650680 and five other SNPs including rs7216389 (P = 0.019,0.034), whereas atopy was associated only with rs11650680 (P = 0.0004). Linear regression revealed the covariates for plasma total IgE to be significant for rs11650680 (P = 0.008,0.0002). Haplotypic associations were found with atopy and increased plasma total IgE, with the respective odds ratios and 95% confidence intervals for TTTCCGTT haplotype to be 0.21 and 0.09,0.52 (P = 0.0002) and 0.41 and 0.18,0.90 (P = 0.025). Conclusion:, Childhood asthma and atopy are associated with chromosome 17q21 in Chinese, but such association may involve genes other than ORMDL3 in this region. [source] Virulence genes in verocytotoxigenic Escherichia coli strains isolated from humans and cattle,APMIS, Issue 9 2005C. WELINDER-OLSSON Verocytotoxigenic Escherichia coli (VTEC) causing diarrhoea, haemorrhagic colitis and haemolytic-uremic syndrome usually have additional traits such as the adhesin intimin and a large plasmid that seems to increase virulence. There are, however, isolates of VTEC causing serious symptoms that do not harbour these traits. In the present study we have used PCR with primers detecting adhesin genes other than eaeA, namely fimA, papC, sfaD/sfaE and daaE. We have also used PCR to detect the genes hlyA and iutA that besides the plasmid-borne gene E-hly possibly support the bacterial access to iron. The aim of the study was to identify and compare the presence of virulence genes in VTEC isolates of human and cattle origin. The main finding was that the absence of E-hly might be compensated for by the gene iutA coding for aerobactin or hlyA coding for ,-haemolysin as 94% of the human VTEC isolates had at least one of these genes. Interestingly, only 45% of VTEC isolated from cattle had any of these genes. We propose that this might be the reason for the relatively low incidence of symptomatic VTEC infections among humans in relation to the high number of VTEC among cattle. [source] Identification of previously unrecognized predisposing factors for ankylosing spondylitis from analysis of HLA,B27 extended haplotypes in sardiniaARTHRITIS & RHEUMATISM, Issue 8 2007Isabella Cascino Objective To define the contribution of HLA genes other than HLA,B27 in conferring susceptibility to ankylosing spondylitis (AS), through analysis of HLA,B27 haplotypes in Sardinian subjects. Methods Ninety-eight patients with AS, 133 HLA,B27,positive controls (of whom 33 were positive for HLA,B*2709), and 190 randomly selected controls were genotyped for microsatellites and single-nucleotide polymorphisms (SNPs) spanning the HLA region. Results Haplotypes carrying either the B*2705 or the B*2709 allele were found to share a conserved region downstream of the HLA,B gene and a functional polymorphism in the HLA,E gene (R128G), while differing in all other markers. Notably, the presence of an A at SNP rs1264457, encoding for Arg-128, was significantly increased in the cohort of patients (P = 6 × 10,6, corrected P = 3 × 10,5) but not in B*2705- or B*2709-positive controls. Comparing the alleles co-occurring at each HLA marker, we identified a region differentiating patients with AS and B*2705-matched controls. In particular, there was a markedly increased prevalence of heterozygosity at rs1264457 among B27-positive controls (74%, versus 47% in patients and 54% in random controls), suggesting a protective role of G128 in AS. Moreover, other markers around the HLA,B gene were also differentially represented. Conclusion These results demonstrate a significant difference in the frequency of some HLA markers between AS patients and B*2705-positive controls, which could be attributed to the opposite chromosome. In particular, the differential distribution of a functional polymorphism in the HLA,E gene suggests a possible role of natural killer function in AS pathogenesis. [source] The effect of plant cytokinin hormones on the production of ethylene, nitric oxide, and protein nitrotyrosine in ageing tobacco leavesBIOFACTORS, Issue 1-4 2006N. Wilhelmová Abstract Transgenic plants with genetically increased or decreased levels of cytokinins were used to investigate the effect of cytokinin level on the production of ethylene, a plant hormone with suggested role in senescence, and the production of nitric oxide, potentially important signalling and regulatory molecule. The production of these gases was followed during the course of leaf development and senescence. The production of ethylene and nitric oxide is under genetic control of genes other than those involved in regulation of senescence. The difference in basic ethylene and NO levels in different tobacco cultivars was higher than their changes in senescence. The results of this study did not indicate a direct link between ethylene production and cytokinin levels. However, there was a decreased production of NO in senescent leaves. Low cytokinins level was associated with increased NO production during leaf development. Protein nitrotyrosine proved to be a better indicator of the reactive nitrogen species than measuring of the NO production. Higher nitrotyrosine concentrations were found in insoluble proteins than in the soluble ones, pointing to membrane proteins as the primary targets of the reactive nitrogen species. In plants with elevated cytokinin levels the content of nitrated proteins decreased both in soluble and insoluble fractions. This finding indicates an antioxidative function of cytokinins against reactive nitrogen species. [source] | |||||||||||||