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1.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

2.
Glutelin is the most significant seed storage protein and is regarded as an important nutrient quality trait in rice. Research on the genetic basis of the glutelin content distinction in rice will provide more choices for the diets of people with kidney disease and diabetes. The GluA and GluB1 genes play important roles in the process of glutelin synthesis. In this study, 128 Japonica rice accessions with wide geographic distributions were collected to construct the association panel. Among all the 128 accessions, both sequences of the GluA and GluB1 genes were obtained, and nucleotide polymorphisms were detected. A total of 46 SNPs and eight InDels, six SNPs and four InDels were found in the GluA and GluB1 gene sequences, respectively. Eight haplotypes and two haplotypes were classified based on the SNPs in the coding region of the GluA and GluB1 genes, respectively. Moreover, the association of the polymorphic sites in the two genes with glutelin content in the tested population was estimated. The results revealed that five SNPs in the GluA gene, one SNP and one InDel in the GluB1 gene were associated with glutelin content at a significant level (P < 0.01). Corresponding markers were also designed to check the alleles of GluA and GluB1 genes. These results suggested that polymorphisms in the GluA and GluB1 genes in rice could be utilized in molecular marker-assisted selection to improve the nutrient quality of rice breeding programmes.  相似文献   

3.
4.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.  相似文献   

5.

Key message

Arabidopsis det1 mutants exhibit salt and osmotic stress resistant germination. This phenotype requires HY5, ABF1, ABF3, and ABF4.

Abstract

While DE-ETIOLATED 1 (DET1) is well known as a negative regulator of light development, here we describe how det1 mutants also exhibit altered responses to salt and osmotic stress, specifically salt and mannitol resistant germination. LONG HYPOCOTYL 5 (HY5) positively regulates both light and abscisic acid (ABA) signalling. We found that hy5 suppressed the det1 salt and mannitol resistant germination phenotype, thus, det1 stress resistant germination requires HY5. We then queried publically available microarray datasets to identify genes downstream of HY5 that were differentially expressed in det1 mutants. Our analysis revealed that ABA regulated genes, including ABA RESPONSIVE ELEMENT BINDING FACTOR 3 (ABF3), are downregulated in det1 seedlings. We found that ABF3 is induced by salt in wildtype seeds, while homologues ABF4 and ABF1 are repressed, and all three genes are underexpressed in det1 seeds. We then investigated the role of ABF3, ABF4, and ABF1 in det1 phenotypes. Double mutant analysis showed that abf3, abf4, and abf1 all suppress the det1 salt/osmotic stress resistant germination phenotype. In addition, abf1 suppressed det1 rapid water loss and open stomata phenotypes. Thus interactions between ABF genes contribute to det1 salt/osmotic stress response phenotypes.
  相似文献   

6.
Our studies have shown that the genotype and allele frequencies of polymorphisms G(?1607)GG of MMP1 gene, C(?1562)T of MMP9 gene, and A(?82)G of MMP12 gene do not significantly differ in the samples of chronic obstructive pulmonary disease (COPD) patients (N = 318) and healthy controls (N = 319) dwelling in Bashkortostan Republic. However, association of (?1562)T allele of the MMP9 gene with the severity of COPD disease progression has been revealed. In COPD patients at stage 4 of the disease, the frequency of allele T was significantly higher that in patients with the stages 2 and 3 (15.89% versus 8.38%; χ2 = 7.804; d.f. = 1; P = 0.005; OR = 2.06 95% CI 1.22–3.49). The distribution of the genotype frequencies of C(?1562)T polymorphism of MMP9 gene significantly differed between the patients with various COPD severity (χ2 = 9.849; d.f. = 2; P = 0.007). The individuals with rare genotype TT were revealed only among patients with severe COPD form (3.97% versus 0%; χ2 = 4.78; P = 0.029; P cor = 0.058). Analysis of this polymorphism in patients with early COPD onset (younger than 55 years old) has shown a significant increase in the allele T frequency in the group of patients with severe COPD (stage 4 according to GOLD) compared to the patients of the same age but with less severe COPD progression (χ2 = 5.26; d.f. = 1; P = 0.022). As the major clinical characteristics of stage 4 COPD is the development of pulmonary emphysema as well as bronchial walls deformation, we suggest that the increased expression of MMP9 gene caused by genetic polymorphism in the gene promoter is important in the early development of serious complications of the disease.  相似文献   

7.
The B subfamily of ATP-binding cassette (ABC) proteins (ABCB) plays a vital role in auxin efflux. However, no systematic study has been done in apple. In this study, we performed genomewide identification and expression analyses of the ABCB family in Malus domestica for the first time. We identified a total of 25 apple ABCBs that were divided into three clusters based on the phylogenetic analysis. Most ABCBs within the same cluster demonstrated a similar exon–intron organization. Additionally, the digital expression profiles of ABCB genes shed light on their functional divergence. ABCB1 and ABCB19 are two well-studied auxin efflux carrier genes, and we found that their expression levels are higher in young shoots of M106 than in young shoots of M9. Since young shoots are the main source of auxin synthesis and auxin efflux involves in tree height control. This suggests that ABCB1 and ABCB19 may also take a part in the auxin efflux and tree height control in apple.  相似文献   

8.
In addition to the already known cagA gene, novel genetic markers have been associated with Helicobacter pylori (H. pylori) virulence: the dupA and vacAi genes. These genes might play an important role as specific markers to determine the clinical outcome of the disease, especially the vacAi gene, which has been expected to be a good marker of severe pathologies like gastric adenocarcinoma. In the present study, the association of cagA, dupA, and vacAi genes with gastroduodenal pathologies in Chilean patients was studied. One hundred and thirty-two patients positive for H. pylori were divided into two groups—non-severe and severe gastric pathologies—and investigated for the presence of cagA, dupA, and vacAi H. pylori virulence genes by PCR. The cagA gene was detected in 20/132 patients (15.2%), the vacAi1 gene was detected in 54/132 patients (40.9%), the vacAi2 gene was detected in 26/132 patients (19.7%), and the dupA gene was detected in 50/132 (37.9%) patients. Logistic regression model analysis showed that the vacAi1 isoform gene in the infected strains and the severity of the diseases outcome were highly associated, causing severe gastric damage that may lead to gastric cancer (p < 0.0001; OR = 8.75; 95% CI 3.54–21.64). Conversely, cagA (p = 0.3507; OR = 1.62; 95% CI 0.59–4.45) and vacAi2 (p = 0.0114; OR = 3.09; 95% CI 1.26–7.60) genes were not associated with damage, while the dupA gene was associated significantly with non-severe clinical outcome (p = 0.0032; OR = 0.25; 95% CI 0.09–0.65). In addition, dupA gene exerts protection against severe gastric pathologies induced by vacAi1 by delaying the outcome of the disease by approximately 20 years.  相似文献   

9.
To study the association with diabetes mellitus type 1, we analyzed the distribution of allele and genotype frequencies of polymorphic marker rs2292239 of ERBB3 gene, encoding epidermal growth factor receptor type 3 and polymorphic marker rs3184504 of SH2B3 gene, encoding adaptor protein LNK. The study included groups of T1DM patients and unrelated controls of Russian origin. Genotyping was performed using RFLP and real-time amplification methods. No statistically significant association with type 1 diabetes was found for the polymorphic marker rs2292239 of ERBB3, while the analysis of the distribution of allele and genotype frequencies of the polymorphic marker rs3184504 of SH2B3 gene revealed the association with T1DM in the Russian population.  相似文献   

10.
Tumor necrosis factor (TNF) plays an important role in the pathogenesis of rheumatoid arthritis (RA). Different genetic variants including the TNF ?308G/A polymorphism are associated with RA susceptibility. However, these findings have not been replicated in all populations. The aim of this study was to determine whether the TNF ?1031T/C (rs1799964), ?376G/A (rs1800750), ?308G/A (rs1800629) ?238G/A (rs361525), and TNFR1 ?609G/T polymorphisms are associated with RA susceptibility in a sample of Mexican patients. Our study included 499 patients with RA and 492 healthy controls. The genotypes of the TNF polymorphisms were obtained using TaqMan assay. The genotype and allele frequencies of the TNF ?1031T/C, ?376G/A, ?308G/A, ?238G/A, and TNFR1 ?609G/T polymorphisms were similar among RA cases versus healthy controls, and no association with RA susceptibility was identified. Our results suggest that the TNF ?1031T/C, ?376G/A, ?308G/A, ?238G/A, and TNFR1 ?609G/T polymorphisms are not associated with RA susceptibility in a sample of Mexican patients.  相似文献   

11.
The diversity of the antibody response is achieved, in part, by rearrangement of different immunoglobulin (Ig) genes. The Ig heavy chain is made up of a variable region (IGHV), a diversity region (IGHD) and a joining region (IGHJ). Human germline IGHV genes have been grouped into seven multigene subgroups. Size and usage of these subgroups is not equal, the IGHV3 subgroup is the most commonly used (36%), followed by IGHV1/7 (26%), then IGHV4, IGHV5, IGHV2, IGHV6 (15%, 12%, 4%, 3% respectively). The rhesus macaque (Macaca mulatta) is a useful non-human primate model for studies of infection and the database of germline Ig genes for the macaque is gradually growing to become a useful tool in the study of B-cell responses. The proportions of IGHV subgroup usage in the macaque are similar to those in man. Representatives from IGHV3 and IGHV4 subgroups for the macaque have been published, as have germline sequences of the IGHD and IGHJ genes. However, to date there have been no sequences published from the second largest IGHV subgroup, IGHV1. We report the isolation and sequencing of a genomic fragment containing an IGHV1 gene from the macaque. Polymerase chain reaction (PCR) primers designed from this sequence enabled us to amplify and sequence 25 new IGHV1 germline genes. We also isolated two IGHV7 genes, using the same primers, and two IGHV5 genes, using human IGHV5 primers.  相似文献   

12.
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.  相似文献   

13.
Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.  相似文献   

14.
Several studies focused on investigating genetic polymorphisms in order to estimate genetic contribution to lung cancer often showed conflicting results. In this study, we investigated the role of GSTM1, GSTT1, GSTP1 exon 5 and exon 6 polymorphisms on developing lung cancer and histological subtypes in 213 lung cancer patients and 231 controls. GSTM1 null, GSTT1 null, and GSTP1 exon 5 variant genotypes did not show a significant risk for developing lung cancer overall. Significant association was noted between GSTP1 exon 6 variant genotypes and overall lung cancer risk (OR 2.17, 95% CI 1.25–3.78; P = 0.006). These results show that GSTP1 exon 6 polymorphism might be an important factor in determining lung cancer susceptibility in a Turkish population.  相似文献   

15.
PCR-RFLP analysis was performed for 391 cases and 514 control individuals to analyze the contribution of polymorphisms of the matrix metalloproteinase genes MMP1 (−1607 G>GG, rs1799750; −519 A>G, rs494379), MMP2 (−735 C>T, rs2285053), MMP3 (−1171 5A>6A, rs35068180), MMP9 (−1562 C>T, rs3918242; 2660A>G, rs17576), MMP12 (−82 A>G, rs2276109), the disintegrin and metalloproteinase 33 gene ADAM33 (12418 A>G, rs2280091; 13491 C>G, rs2787094), and tissue inhibitors of metalloproteinase genes TIMP2 (−418 G>C, rs8179090) and TIMP3 (−1296 T>C, rs9619311) to chronic obstructive pulmonary disease. Significant association with increased rick of chronic obstructive pulmonary disease was observed for the 6A6A genotype of the MMP3 −1171 5A>6A polymorphism (OR = 2.49, P adj = 0.003979, P cor = 0.0358 adjusted for age, sex, smoke pack-years, ethnicity) and for the G-G haplotype of ADAM33 polymorphisms 13491 C>G and 12418 A>G (OR = 0.39, P adj = 0.0012, P cor = 0.006). Significant interactions were detected between the smoking status and ADAM33 12418 A >G (P interact = 0.026) and TIMP3 −1296 T>C (P interact = 0.044). The risk of emphysema was increased in GG homozygotes by ADAM33 13491 C>G and a risk of emphysema was found (OR = 1.74, P adj = 0.013, P cor = 0.117). The severity of chronic obstructive pulmonary disease was modified by MMP9 −1562 C>T in the additive model (OR = 1.883, P adj = 0.028, P cor = 0.252). Thus, polymorphisms of MMP3, MMP9, ADAM33, and TIMP3 can be considered important risk factors for the development and progression of chronic obstructive pulmonary disease; in addition, pathogenetically significant gene-environment interactions were identified. These data contribute to the understanding of hereditary predisposition to chronic obstructive pulmonary disease.  相似文献   

16.
A genetic transformation system has been developed for callus cells of Crataegus aronia using Agrobacterium tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with 5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this is the first time to report an Agrobacterium-mediated transformation system in Crataegus aronia.  相似文献   

17.
To elucidate the physiological adaptation of Escherichia coli due to cra gene knockout, a total of 3,911 gene expressions were investigated by DNA microarray for continuous culture. About 50 genes were differentially regulated for the cra mutant. TCA cycle and glyoxylate shunt were down-regulated, while pentose phosphate (PP) pathway and Entner Doudoroff (ED) pathway were up-regulated in the cra mutant. The glucose uptake rate and the acetate production rate were increased with less acetate consumption for the cra mutant. To identify the genes controlled by Cra protein, the Cra recognition weight matrix from foot-printing data was developed and used to scan the whole genome. Several new Cra-binding sites were found, and some of the result was consistent with the DNA microarray data. The ED pathway was active in the cra mutant; we constructed cra.edd double genes knockout mutant to block this pathway, where the acetate overflowed due to the down-regulation of aceA,B and icd gene expressions. Then we further constructed cra.edd.iclR triple genes knockout mutant to direct the carbon flow through the glyoxylate pathway. The cra.edd.iclR mutant showed the least acetate production, resulting in the highest cell yield together with the activation of the glycolysis pathway, but the glucose consumption rate could not be improved. Dayanidhi Sarkar and Khandaker Al Zaid Siddiquee have contributed equally.  相似文献   

18.

Introduction  

Recent genome-wide and candidate gene association studies in large numbers of systemic lupus erythematosus (SLE) patients have suggested approximately 30 susceptibility genes. These genes are involved in three types of biological processes, including immune complex processing, toll-like receptor function and type I interferon production, and immune signal transduction in lymphocytes, and they may contribute to the pathogenesis of SLE. To better understand the genetic risk factors of SLE, we investigated the associations of seven SLE susceptibility genes in a Chinese population, including FCGR3A, FCGR2A, TNFAIP3, TLR9, TREX1, ETS1 and TNIP1.  相似文献   

19.
Pisum sativum L., the garden pea crop plant, is serving as the unique model for genetic analyses of morphogenetic development of stipule, the lateral organ formed on either side of the junction of leafblade petiole and stem at nodes. The stipule reduced (st) and cochleata (coch) stipule mutations and afila (af), tendril-less (tl), multifoliate-pinna (mfp) and unifoliata-tendrilled acacia (uni-tac) leafblade mutations were variously combined and the recombinant genotypes were quantitatively phenotyped for stipule morphology at both vegetative and reproductive nodes. The observations suggest a role of master regulator to COCH in stipule development. COCH is essential for initiation, growth and development of stipule, represses the UNI-TAC, AF, TL and MFP led leafblade-like morphogenetic pathway for compound stipule and together with ST mediates the developmental pathway for peltate-shaped simple wild-type stipule. It is also shown that stipule is an autonomous lateral organ, like a leafblade and secondary inflorescence.  相似文献   

20.
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