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1.
Anionic peroxidase isoenzymes, separated on acrylamide gels, were examined in two flax genotrophs and in their reciprocal F2 hybrids. Isoenzyme 1 exhibited a significant difference in Rm between stem base and apex and there was a gradient of decreasing Rm and activity between base and apex. Isoenzyme 2 displayed only the activity gradient. The parents differed significantly in the Rm's and activities of isoenzymes 1 and 2, and the F2's showed complete dominance of the L parent for Rm, with activities being approximately intermediate. 相似文献
2.
Reciprocal and nonreciprocal recombination at the glucocerebrosidase gene region: implications for complexity in Gaucher disease 下载免费PDF全文
Tayebi N Stubblefield BK Park JK Orvisky E Walker JM LaMarca ME Sidransky E 《American journal of human genetics》2003,72(3):519-534
Gaucher disease results from an autosomal recessive deficiency of the lysosomal enzyme glucocerebrosidase. The glucocerebrosidase gene is located in a gene-rich region of 1q21 that contains six genes and two pseudogenes within 75 kb. The presence of contiguous, highly homologous pseudogenes for both glucocerebrosidase and metaxin at the locus increases the likelihood of DNA rearrangements in this region. These recombinations can complicate genotyping in patients with Gaucher disease and contribute to the difficulty in interpreting genotype-phenotype correlations in this disorder. In the present study, DNA samples from 240 patients with Gaucher disease were examined using several complementary approaches to identify and characterize recombinant alleles, including direct sequencing, long-template polymerase chain reaction, polymorphic microsatellite repeats, and Southern blots. Among the 480 alleles studied, 59 recombinant alleles were identified, including 34 gene conversions, 18 fusions, and 7 downstream duplications. Twenty-two percent of the patients evaluated had at least one recombinant allele. Twenty-six recombinant alleles were found among 310 alleles from patients with type 1 disease, 18 among 74 alleles from patients with type 2 disease, and 15 among 96 alleles from patients with type 3 disease. Several patients carried two recombinations or mutations on the same allele. Generally, alleles resulting from nonreciprocal recombination (gene conversion) could be distinguished from those arising by reciprocal recombination (crossover and exchange), and the length of the converted sequence was determined. Homozygosity for a recombinant allele was associated with early lethality. Ten different sites of crossover and a shared pentamer motif sequence (CACCA) that could be a hotspot for recombination were identified. These findings contribute to a better understanding of genotype-phenotype relationships in Gaucher disease and may provide insights into the mechanisms of DNA rearrangement in other disorders. 相似文献
3.
Vasiliu D Razi N Zhang Y Jacobsen N Allin K Liu X Hoffmann J Bohorov O Blixt O 《Carbohydrate research》2006,341(10):1447-1457
Poly-N-acetyllactosamines (pLNs) are common terminal sugars of many N- and O-linked glycan structures present in glycoproteins and glycolipids. Utilizing various glycosyltransferases, we developed new and efficient chemoenzymatic methods for the synthesis of pLNs in gram-scale. Specifically, the use of sialyltransferases and fucosyltransferases enabled us to synthesize and purify 24 blood group and tumor-associated pLN derivatives with alpha-(2-->3)- and alpha-(2-->6)-linked sialic acid, as well as with alpha-(1-->2)- and alpha-(1-->3)-linked fucose. All synthesized derivatives were linked to a short 2-azidoethyl spacer for further modification. 相似文献
4.
Bahmani Bahareh Amini-bayat Zahra Ranjbar Mohammad Mehdi Bakhtiari Nahid Zarnani Amir-Hassan 《International journal of peptide research and therapeutics》2021,27(1):365-378
International Journal of Peptide Research and Therapeutics - Cervical cancer is the second most common leading cause of women's death due to cancer worldwide, about 528,000 patients’... 相似文献
5.
Application of Bacillus pumilus as a potential biocontrol agent of Fusarium wilt of tomato 总被引:1,自引:0,他引:1
Nahid Heidarzadeh Sareh Baghaee-Ravari 《Archives Of Phytopathology And Plant Protection》2013,46(13-16):841-849
The current study aimed at evaluating the possibility of native Bacillus pumilus species to control Fusarium wilt in tomato and examine its effect on plant growth. Biocontrol traits of B. pumilus strains, biofilm assay, root colonisation and in vivo studies under pot conditions were determined. Strain ToIrMA-KC806242 formed biofilm efficiently and could colonise and survive on tomato rhizosphere (3.1 × 104 CFU/g of root). The amount of auxin production was recorded 29.7 μg/ml at the 96th hour of incubation. Siderophore production was determined positive, while ToIrMA was not able to solubilise phosphate compounds or produce cyanide hydrogen. Statistical analysis of data revealed that the increase in root and shoot length was recorded 60 and 84%, respectively, over control. In addition, about 73% reduction in disease incidence was determined in vivo experiments. In conclusion, this study suggests B. pumilus ToIrMA strain as a possible biocontrol agent in the field experiments. 相似文献
6.
Jamal S.M. Sabir Abdelfatteh El Omri Noor A. Shaik Babajan Banaganapalli Nahid H. Hajrah Houda Zrelli Leila Arfaoui Zuhier A. Awan Abdulkader M. Shaikh Omar Arif Mohammed Mona G. Alharbi Alawiah M. Alhebshi Robert K. Jansen Muhummadh Khan 《Saudi Journal of Biological Sciences》2019,26(7):1338-1343
Obesity is a multifactorial metabolic disorder characterized by low grade chronic inflammation. Rare and novel mutations in genes which are vital in several key pathways have been reported to alter the energy expenditure which regulates body weight. The TP53 or p53 gene plays a prominent role in regulating various metabolic activities such as glycolysis, lipolysis, and glycogen synthesis. Recent genome-wide association studies reported that tumor suppressor gene p53 variants play a critical role in the predisposition of type 2 diabetes and obesity. Till date, no reports are available from the Arabian population; hence the present study was intended to assess the association between p53 variants with risk of obesity development in the Saudi population. We have selected three p53 polymorphisms, rs1642785 (C > G), and rs9894946 (A > G), and rs1042522 (Pro72Arg; C > G) and assessed their association with obesity risk in the Saudi population. Phenotypic and biochemical parameters were also evaluated to check their association with p53 genotypes and obesity. Genotyping was carried out on 136 obese and 122 normal samples. We observed that there is significantly increased prevalence p52 Pro72Arg (rs1042522) polymorphism in obese persons when compared to controls at GG genotype in overall comparison (OR: 2.169, 95% CI: 1.086-4.334, p = 0.02716). Male obese subjects showed three-fold higher risk at GG genotype (OR: 3.275, 95% CI: 1.230-8.716, p = 0.01560) and two-fold risk at G allele (OR: 1.827, 95% CI: 1.128-2.958, p = 0.01388) of p53 variant Pro72Arg respectively. This variant has also shown significant influence on cholesterol, LDL level, and random insulin levels in obese subjects (p ≤ 0.05). In conclusion, p53 Pro72Arg variant is highly prevalent among obese individuals and may act as a genetic modifier for obesity development among Saudis. 相似文献
7.
Mominul Islam Nahid Frode Fossøy Bård G. Stokke Sajeda Begum Eivin Røskaft 《Bird Study》2019,66(1):141-144
House Crows Corvus splendens lay eggs with bluish-green ground colour and black or brown blotches and only one egg morph was believed to exist. Here, we confirm the existence of an immaculate, spotless blue egg morph that is clearly different from the regular egg morph. 相似文献
8.
Shahla Borzouei Rouhallah Sharifi Nahid Moarrefzadeh 《Journal of Phytopathology》2019,167(10):567-575
Rhizosphere dwelling bacteria can increase plant resistance to biotic and abiotic stresses, and they promote plant growth through various mechanisms. In this study, three bioassays were conducted including the following: (a) screening for effective bacterial isolates in the suppression of broomrape, (b) evaluating induced systemic resistance against broomrape and (c) comparing the selected bacterium isolate with plant chemical inducers. Fifteen plant growth‐promoting rhizobacteria (PGPR) were examined to assess their biocontrol potential against Egyptian broomrape (Phelipanche aegyptiaca). Ten isolates significantly reduced the broomrape biomass compared to the control. The Lysinibacillus boronitolerans B124 reduced the dry weight of broomrape plants from 2.15 g in control to 0.45 g. Bacillus megaterium B6 was the best isolate in reducing the number of broomrape tubercles. In addition, the activity of three selected bacterial isolates was investigated in induced systemic resistance to broomrape by split‐root method. The Bacillus pumilus INR7 reduced the number of visible broomrape tubercles by 90%, and B. megaterium B71 and L. boronitolerans B124 were the next two in rank. Compared with the control, L. boronitolerans B124 reduced the dry weight of broomrape from 1.49 g in control to 0.39 g. In a subsequent experiment, L. boronitolerans B124 was evaluated along with some resistance‐inducing volatile compounds. Lysinibacillus boronitolerans B124 decreased the number of broomrapes by 87% on average, while the lowest dry weight of broomrape was observed in methyl jasmonate treatment. In conclusion, PGPR have considerable potential to be used in the integrated management of broomrape. It is also possible to use a mixture of rhizobacteria and defence inducers, such as biogenic volatiles as a promising approach in the management of this noxious parasitic weed. 相似文献
9.
10.
Binnur Eroglu Donald E. Kimbler Junfeng Pang Justin Choi Demetrius Moskophidis Nathan Yanasak Krishnan M. Dhandapani Nahid F. Mivechi 《Journal of neurochemistry》2014,130(5):626-641
Traumatic brain injury (TBI) induces severe harm and disability in many accident victims and combat‐related activities. The heat‐shock proteins Hsp70/Hsp110 protect cells against death and ischemic damage. In this study, we used mice deficient in Hsp110 or Hsp70 to examine their potential requirement following TBI. Data indicate that loss of Hsp110 or Hsp70 increases brain injury and death of neurons. One of the mechanisms underlying the increased cell death observed in the absence of Hsp110 and Hsp70 following TBI is the increased expression of reactive oxygen species‐induced p53 target genes Pig1, Pig8, and Pig12. To examine whether drugs that increase the levels of Hsp70/Hsp110 can protect cells against TBI, we subjected mice to TBI and administered Celastrol or BGP‐15. In contrast to Hsp110‐ or Hsp70i‐deficient mice that were not protected following TBI and Celastrol treatment, there was a significant improvement of wild‐type mice following administration of these drugs during the first week following TBI. In addition, assessment of neurological injury shows significant improvement in contextual and cued fear conditioning tests and beam balance in wild‐type mice that were treated with Celastrol or BGP‐15 following TBI compared to TBI‐treated mice. These studies indicate a significant role of Hsp70/Hsp110 in neuronal survival following TBI and the beneficial effects of Hsp70/Hsp110 inducers toward reducing the pathological consequences of TBI.