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1.
Random Amplified Polymorphic DNA Variation among and within Selected Ixora (Rubiaceae) Populations and Mutants 总被引:1,自引:0,他引:1
RAJASEGER G.; TAN H. T. W.; TURNER I. M.; SAW L. G.; KUMAR P. P. 《Annals of botany》1999,84(2):253-257
Random amplified polymorphic DNA (RAPD) analysis was used tostudy variation among and within selectedIxora (Rubiaceae) populationsand mutants. Six populations of I. congesta yielded identicalbanding patterns suggesting genetic uniformity of this species.However, six populations of I. coccinea varieties (three red-flowered,two yellow-flowered and one red-flowered wild-type) exhibitedinfraspecific differences in RAPD profiles. Small and largeleaves of an atavistic mutant cultivar of I. coccinea were alsosubjected to RAPD analysis. An extra band was amplified in thelarge leaves that was absent in small leaves, suggesting thatthe phenotypic alteration in this taxon is due to genetic mutationrather than epigenetic changes. Similarly, an extra band wasdetected in the white sectors of I. Variegated compared to thegreen sectors, suggesting that the shoot apical meristems ofthis cultivar exist as a genetic chimera. DNA gel blot hybridizationwas performed to confirm the specificities of selected bands.Our study indicates that differences among individuals of variouspopulations and mutants may be detected using RAPD markers.Copyright 1999 Annals of Botany Company Ixora L., variegated variety, RAPD fingerprinting, DNA gel blot, intraspecific genetic similarity, atavistic mutant. 相似文献
2.
Haiyan Miao Jingjing Lu Yibing Guo Hongquan Qiu Yu Zhang Xihao Yao Xiaohong Li Yuhua Lu 《Journal of cellular and molecular medicine》2021,25(7):3654-3664
Pancreatic ductal adenocarcinoma (PDAC) is an invasive and aggressive cancer that remains a major threat to human health across the globe. Despite advances in cancer treatments and diagnosis, the prognosis of PDAC patients remains poor. New and more effective PDAC therapies are therefore urgently required. In this study, we identified a novel host factor, namely the LncRNA TP73-AS1, as overexpressed in PDAC tissues compared to adjacent healthy tissue samples. The overexpression of TP-73-AS1 was found to correlate with both PDAC stage and lymph node metastasis. To reveal its role in PDCA, we targeted TP73-AS1 using LnRNA inhibitors in a range of pancreatic cancer (PC) cell lines. We found that the inhibition of TP73-AS1 led to a loss of MMP14 expression in PC cells and significantly inhibited their migratory and invasive capacity. No effects of TP73-AS1 on cell survival or proliferation were observed. Mechanistically, we found that TP73-AS1 suppressed the expression of the known oncogenic miR-200a. Taken together, these data highlight the prognostic potential of TP73-AS1 for PC patients and highlight it as a potential anti-PDAC therapeutic target. 相似文献
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A comparative study on tyrosine oxidation was made with a pure cationic and anionic peroxidase from peanut cell culture medium. The results showed that both isozymes possessed almost identical capacity to oxidize tyrosine to dityrosine, isodityrosine and polytyrosine with the main difference being the pH optimum (pH 4 for the anionic and pH 7 for the cationic isozyme). Variation of reaction time after 1.5 h incubation had little effect on the quantity and quality of the oxidation products. On the other hand, increase of enzyme units correspondingly increased tyrosine-oxidation. The removal of heme and carbohydrate moieties from the holoenzyme arrested the reaction thereby suggesting the role played by these moieties in stabilizing the active site of peroxidase isoenzymes. Isolated cell wall extracts catalyzed the tyrosine-oxidation equally well as the purified peroxidase. Even though polyclonal antibodies against anionic peroxidase inhibited the in vitro tyrosine reaction they did not affect the tyrosine oxidation by the cell walls, while the cationic antibodies did.Abbreviations A.PRX
anionic peanut peroxidase
- C.PRX
cationic peanut peroxidase
- PcAb
polyclonal antibodies
- ELISA
enzyme-linked-immuno-sorbent-assay
- TFMS
trifluoromethane sulfonic acid 相似文献
6.
不同利用方式下稻田效益的综合评价 总被引:1,自引:0,他引:1
一、引言评价是多目标系统优化和决策的基础。和任何其他农业生态系统一样,稻田生态系统具有多目标、多功能的特点,单项指标难以反映系统的优劣。目前,川东南地区稻田开发利用方式多种多样,但效益评价主要是采用简单的比较分析或粗放的定性描述,尚未形成系统的 相似文献
7.
汉滩病毒核壳蛋白(NP)在杆状病毒系统的表达及其免疫原性研究 总被引:11,自引:0,他引:11
应用杆状病毒表达载体成功地表达了汉滩病毒76-118株(HTNV)核壳蛋白,将HTNVS基因插入杆状病毒转染质粒pAcYMIB的多角体基因启动子下游附近,与经Bsu361酶切线性化的杆状病毒(AcVEPA)DNA共同转染S19细胞,经空斑筛选获得了高效表达NP的重组杆状病毒(AcVHanS)。经SDS-PAGE和Western blot证实,表达产物与HTNV毒粒NP分子量均为50KD左右,紫外扫 相似文献
8.
Xiaohong Zheng Tony D'Amore Inge Russell Graham G. Stewart 《Journal of industrial microbiology & biotechnology》1994,13(3):159-166
Summary Maltotriose transport was studied in two brewer's yeast strains, an ale strain 3001 and a lager strain 3021, using laboratory-synthesized14C-maltotriose. The maltotriose transport systems preferred a lower pH (pH 4.3) to a higher pH (pH 6.6). Two maltotriose transport affinity systems have been indentified. The high affinity system hasK
m values of 1.3 mM for strain 3021 and 1.4 mM for strain 3001. The low affinity competitively inhibited by maltose and glucose withK
i values of 58 mM and 177 mM. respectively, for strain 3021, and 55 mM and 147 mM, respectively, for strain 3001. Cells grown in maltotriose and maltose had higher maltotriose and maltose transport rates, and cells grown in glucose had lower maltortriose and maltose transport rates. Early-logarithmic phase cells transported glucose faster than either maltose or maltotriose. Cells harvested later in the growth phase had increased maltotriose and maltose transport activity. Neither strain exhibited significant differences with respect to maltose and maltotriose transport activity. 相似文献
9.
Bradykinin (BK) is a peptide hormone with sequence Arg1-Pro2-Pro3-Gly4-Phe5-Ser6-Pro7-Phe8-Arg9 and has been implicated in a multitude of pathophysiological processes such as the ability to lower systemic blood pressure and stimulate pain. BK analogues having bulky, β-branched D -aliphatic residues at position 7 combined with bulky L -aliphatic residues at position 8 have now been observed to be strong antagonists. Conformational studies based on two-dimensional nmr experiments in methanol/water (80/20 v/v) were carried out on several such active antagonists in a polar solvent. Included in this study were the very active antagonists, [D -Arg0, Hyp3, Thi5, D -Cpg7, Cpg8]-BK [Cpg: α-cyclo-pentyl-glycine; Hyp: trans-4-hydroxy-L -proline; Thi: β-(2-thienyl)-L -alanine] ( I ), [D -Arg0, Hyp3, D -Cpg7, Cpg8] -BK ( II ), as well as its variant with D -Cpg7 replaced by Cpg7, namely [D -Arg0, Hyp3, Cpg7, Cpg8]-BK ( III ). A turn-like structure, which coexists with the extended conformation, was observed between residues 2 and 5 for the most active antagonists I and II , in direct correlation with the peptide activities. No turn-like structure was found for residues 6–9. In peptide III , a turn-like structure was not identified. The existence of a turn at the C-terminal end of bradykinin and its analogues has been predicted by empirical calculations and supported by nmr measurements. But the present nmr study on the most active antagonists ( I , II ) does not support this hypothesis. Instead, the data suggest that a turn-like structure between residues 2 and 5 could be important for antagonist activity. Finally, one weak inhibitor [D -Cpg7]-BK ( IV ) showed no defined secondary structure. © 1993 John Wiley & Sons, Inc. 相似文献
10.
本文应用数量遗传学方法,结合概率运算,从理论上分析了由X连锁基因控制的性状在雌雄群体中的变异情况。表明雄(男)性群体的这类性状遗传变异范围有大于雌(女)性群体的倾向。对这一问题的探讨,将有助于对X连锁基因及所决定性状的遗传特性、进化特点及基因定位等的研究提供新的思路。 相似文献