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51.
52.
《Reproductive biology》2020,20(2):220-228
This experiment was conducted to study the effect of mineral supplementation on seminal plasma minerals level, biochemical constituents and total antioxidant capacity of Osmanabadi bucks. The study comprised of forty healthy bucks, aged five months were randomly assigned to ten groups (n = 4 per group). The control group was fed with a basal diet without any additional mineral supplementation. In addition to basal diet, treatment bucks were supplemented with three graded doses of organic Zinc (Zn) as 20, 40 and 60 mg/kg dry matter (DM); organic Copper (Cu) as 12.5, 25, 37.5 mg/ kg DM and combination of Zn + Cu as Zn20+Cu12.5, Zn40+Cu25, Zn60+Cu37.5 mg /kg DM basis respectively. Minerals were supplemented for 8 months and the separated seminal plasma used for analysis of minerals, biochemical profile, total antioxidant capacity (TAC), lipid peroxidation (LPO), and protein carbonylation (PC). In treatment groups, significantly lower LPO and PC were observed, except Zn60 and Zn60+Cu37.5, where higher malondialdehyde (MDA) (P < 0.05) formed. The TAC was relatively higher (P < 0.05) in Zn20, Zn40, Cu12.5 and Zn60+Cu37.5 than control. The minerals and biochemical parameters were significantly altered and positive relationship was observed among them. From this study, it was concluded that supplemented minerals changed the seminal plasma minerals profile (Zn- 7–13; Cu- 0.5–1.9 mg/L), reduced the stress (LPO and PC of control Vs treatment as 0.3 Vs 0.1 nmol/ml and 25.7 Vs 4.3 nmol protein carbonyl/mg protein), which improved the sperm quality in Zn40, all Cu treatments and Zn60+Cu37.5 groups respectively.  相似文献   
53.
Oxidative stress is considered as a prominent feature of many acute and chronic diseases as well as of the normal aging process. We examined the effects of intra-peritoneal administration of catechins and EGCG as in vivo inhibitors of oxidative stress induced by ozone administration in two groups of Wistar rats. The first group was treated by intra-peritoneal administration of catechins and EGCG after the administration of ozone and the second group was pretreated by intra-peritoneal administration of catechins and EGCG prior to ozone administration. We determined in blood the activity of the enzymes superoxide dismutase and glutathione peroxidase, total antioxidant capacity, levels of copper and zinc and in urine malonaldehyde contents. Ozone administration resulted in significant reduction of glutathione peroxidase activity, plasma zinc levels and plasma and Red Blood Cells antioxidant capacity. Catechins and EGCG upregulate superoxide dismutase activity and maintain plasma and Red Blood Cells antioxidant capacity. Malonaldehyde levels at the end of the study were significantly increased only in the first group. Our data demonstrate that treatment with catechins and EGCG cannot reverse or prevent the effects of oxidative stress although some modulation occurs.  相似文献   
54.
Sixteen Pl and TAC clones assigned to Arabidopsis thaliana chromosome5 were sequenced, and their sequence features were analyzedusing various computer programs. The total length of the sequencesdetermined was 1,013,767 bp. Together with the nucleotide sequencesof 109 clones previously reported, the regions of chromosome5 sequenced so far now total 9,072,622 bp, which presumablycovers approximately one-third of the chromosome. A similaritysearch against the reported gene sequences predicted the presenceof a total of 225 protein-coding genes and/or gene segmentsin the newly sequenced regions, indicating an average gene densityof one gene per 4.5 kb. Introns were identified in 72.4% ofthe potential protein genes for which the entire gene structurewas predicted, and the average number per gene and the averagelength of the introns were 3.3 and 163 bp, respectively. Thesesequence features are essentially identical to those in thepreviously reported sequences. The sequence data and gene informationare available on the World Wide Web database KAOS (Kazusa Arabidopsisdata Opening Site) at http://www.kazusa.or.jp/arabi/.  相似文献   
55.
TAC1, a major quantitative trait locus controlling tiller angle in rice   总被引:10,自引:0,他引:10  
A critical step during rice (Oryza sativa) cultivation is dense planting: a wider tiller angle will increase leaf shade and decrease photosynthesis efficiency, whereas a narrower tiller angle makes for more efficient plant architecture. The molecular basis of tiller angle remains unknown. This research demonstrates that tiller angle is controlled by a major quantitative trait locus, TAC1 (Tiller Angle Control 1). TAC1 was mapped to a 35-kb region on chromosome 9 using a large F(2) population from crosses between an indica rice, IR24, which displays a relatively spread-out plant architecture, and an introgressed line, IL55, derived from japonica rice Asominori, which displays a compact plant architecture with extremely erect tillers. Genetic complementation further identified the TAC1 gene, which harbors three introns in its coding region and a fourth 1.5-kb intron in the 3'-untranslated region. A mutation in the 3'-splicing site of this 1.5-kb intron from 'AGGA' to 'GGGA' decreases the level of tac1, resulting in a compact plant architecture with a tiller angle close to zero. Further sequence verification of the mutation in the 3'-splicing site of the 1.5-kb intron revealed that the tac1 mutation 'GGGA' was present in 88 compact japonica rice accessions and TAC1 with 'AGGA' was present in 21 wild rice accessions and 43 indica rice accessions, all with the spread-out form, indicating that tac1 had been extensively utilized in densely planted rice grown in high-latitude temperate areas and at high altitudes where japonica rice varieties are widely cultivated.  相似文献   
56.
Recent research has shown that BIBAC (binary bacterial artificial chromosome) and TAC (transformation-competent artificial chromosome) vector systems are very useful tools for map-based cloning of agronomically important genes in plant species. We have developed a new TAC vector that is suitable for both dicot and monocot transformation. Using this new TAC vector, we constructed large-insert genomic libraries of tomato and rice. The tomato library contains 96,996 clones (28.3-38.5 kb insert size) and has 3.18 haploid genome equivalents. The rice TAC library has 32.7 kb average insert size and has 9.24 haploid genome equivalents. The quality of these two libraries was tested using PCR to verify genome coverage. Individual clones were characterized to confirm insert integrity by Southern analysis, end sequencing and genetic mapping. To investigate the potential application of these TAC libraries in map-based cloning, TAC constructs containing a 45 kb fragment were introduced into the rice genome via Agrobacterium-mediated transformation. Molecular analysis indicates that the 45 kb fragment was successfully transferred into the rice genome. Although rearrangements of the introduced DNA were detected, 50% of regenerated plants contained at least one intact copy of the 45 kb clone and associated vector sequences. These libraries provide us with a valuable resource to rapidly isolate important genes in tomato and rice.  相似文献   
57.
In the present study, we hypothesized that an appropriate combination of a geomagnetic field (as a static field) and an alternative magnetic field may result in the promotion of maize seedling growth by an alleviation of an excess production of reactive oxygen species. First, we determined the applicable range of frequencies by theoretical calculations, and a combined magnetic field was designed. The seeds were germinated in the magnetic field for 4 days, and the seedlings were allowed to grow in a nutrient solution for another 4 days. The magnetic field-treated maize seeds produced seedlings with a faster growth rate than the control seeds. The activity of superoxide dismutase in the magnetic field-treated seedlings was lower, while the total antioxidant capacity of these seedlings was higher than that of the control group. The maintenance of membrane integrity and a decrease of iron content in the magnetic field-treated seedlings suggest that a combination of both static and alternative magnetic fields promotes the growth of the plants by lowering iron absorption, a reduction in the Fenton chemistry, and lowering the risk of oxidative burst.  相似文献   
58.
Molecular Evolution of the TAC1 Gene from Rice (Oryza sativa L.)   总被引:1,自引:0,他引:1  
Tiller angle is a key feature of the architecture of cultivated rice(Oryza sativa),since it determines planting density and influences rice yield.Our previous work identified Tiller Angle Control 1(TACl) as a major quantitative trait locus that controls rice tiller angle.To further clarify the evolutionary characterization of the TACl gene,we compared a TACl-containing 3164-bp genomic region among 113 cultivated varieties and 48 accessions of wild rice,including 43 accessions of O.rufipogon and five accessions of O.nivara.Only one single nucleotide polymorphism(SNP),a synonymous substitution,was detected in TACl coding regions of the cultivated rice varieties, whereas one synonymous and one nonsynonymous SNP were detected among the TACl coding regions of wild rice accessions.These data indicate that little natural mutation and modification in the TACl coding region occurred within the cultivated rice and its progenitor during evolution.Nucleotide diversities in the TACl gene regions of O.sativa and O.rufipogon of 0.00116 and 0.00112,respectively, further indicate that TACl has been highly conserved during the course of rice domestication.A functional nucleotide polymorphism (FNP) of TACl was only found in the japonica rice group.A neutrality test revealed strong selection,especially in the 3’-flanking region of the TACl coding region containing the FNP in the japonica rice group.However,no selection occurred in the indica and wild-rice groups.A phylogenetic tree derived from TACl sequence analysis suggests that the indica and japonica subspecies arose independently during the domestication of wild rice.  相似文献   
59.
ZR proteins belong to a phylogenetically conserved family of small zinc-ribbon proteins in plastids and mitochondria of higher plants. The function of these proteins is so far unclear. The mitochondrial proteins share sequence similarities with mitochondrial Hsp70 escort proteins (HEP) from Saccharomyces cerevisiae (HEP1) and human. Expression of the mitochondrial ZR protein from Arabidopsis, ZR3, rescued a hep1 knockout mutant from yeast. Accordingly, ZR3 was found to physically interact with mitochondrial Hsp70 from Arabidopsis. Our findings support the idea that mitochondrial and plastidic ZR proteins from higher plants are orthologs of HEP proteins.

Structured summary of protein interactions

ZR3physically interacts with mtHSC70-2 by pull down (View interaction)ZR3physically interacts with mtHSC70-1 by pull down (View interaction)  相似文献   
60.
The identification of candidate genes for significant traits is crucial. In this study, we developed and tested effective and systematic methods based on linkage disequilibrium (LD) for the identification of candidate regions for genes with Mendelian inheritance and those associated with complex traits. Our approach entailed the combination of primary screening using pooled DNA samples based on ΔTAC, secondary screening using an individual typing method and tertiary screening using a permutation test based on the differences in the haplotype frequency between two neighbouring microsatellites. This series of methods was evaluated using horse coat colour traits (chestnut/non-chestnut) as a simple Mendelian inheritance model. In addition, the methods were evaluated using a complex trait model constructed by mixing samples from chestnut and non-chestnut horses. Using both models, the methods could detect the expected regions for the horse coat colour trait. The results revealed that LD extends up to several centimorgans in horses, indicating that whole-genome LD screening in horses could be performed systematically and efficiently by combining the above-mentioned methods. Since genetic maps based on microsatellites have been constructed for many other species, the approaches present here could have wide applicability.  相似文献   
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