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黄淮麦区16个小麦品种(系)的Glu—1,Glu—3和Gli—1位点上的基因多样 … 总被引:7,自引:0,他引:7
16个品种(系)的高分子量麦谷蛋白亚基(HMW-GS)的等位基因频率分别为Glu-Ala(80%),Glu-Alc(12%),Glu-Alb(8%);Glu-B1b(63%)Glu-Blc(31%)Glu-Ble(6%)Glu-Dla(38%),Glu-Dld(50%)Glu-Dlc(12%),16个品种(系)的低分子量麦谷蛋白亚基(LMW-GS)的等位基因频率分别为:Glu-A3a(38%),G 相似文献
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G138P定点突变对葡萄糖异构酶热稳定性的改善 总被引:18,自引:0,他引:18
通过分子设计,确定Gly138为改善葡萄糖异构酶(GI)热稳定性的目标氨基酸。用双引物法对GI基因进行体外定点突变,构建了GI突变体G138P。含突变体的重组质粒pTKD-GIG138P在E.coliK38菌株中表达。GIG138P与野生型GI比较实验表明:(1)GIG138P的热失活半衰期约是野生型GI的2倍;(2)GIG138P的最适反应温度提高了10 ̄12℃;(3)GIG138P的比活与野生 相似文献
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G蛋白对离子通道的调控 总被引:3,自引:0,他引:3
G蛋白对离子通道的调控鲍国斌濮璐裴钢(中国科学院上海细胞生物学研究所,上海200031关键词G蛋白G蛋白偶联受体离子通道G蛋白(Gprotein)由α、β、γ三个亚基组成,位于细胞膜的胞液侧。Gα亚基具有GTP酶活性,使G蛋白偶联受体和效应分子发生可... 相似文献
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用固相合成法合成了有关降钙素基因相关肽CGRP五个肽段。它们的氨基酸顺序分别为:CGRP-1(24-37);CGRP-2(14-37);CGRP-3(9-23);CGRP-4(1-23)和CGRP-5(1-13)。用酶标方法测定了它们的抗原性,发现CGRP-2和CGRP-1能够很好地与抗CGRP抗血清结合。将CGRP-1;CGRP-3和CGRP-5分别免疫兔子,获得的抗血清分别与CGRP进行反应,发现只有抗CGRP-1的抗血清能够与CGRP很好地结合。因此,可以推测CGRP的羧端部分是其免疫活性部位。 相似文献
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从人正常胸主动脉分离硫酸乙酰肝素蛋白聚糖(HSPG),观察其对体外培养的人主动脉平滑肌细胞(HASMC)合成PG的影响。HASMC在不加(对照)或加HSPG(19μg醛酸/ml)的 ̄(35)S-硫酸钠培养液中培养,以标记PG。继之,培养液及细胞层的4mol/L盐酸胍提取液中的PGs经离子交换及凝胶过滤柱层析分离,发现加HSPG后,培养液中的HSPG,硫酸软骨素PG(CSPG)及硫酸皮肤素-硫酸软骨素PG(DSCSPG)均明显增高,而细胞层中仅HSPG和CSPG增高,且加HSPG后细胞层的DSCSPG分子大小有所不同,进一步分析DSCSPG中DS及CS含量发现加HSPG组HASMC细胞层中的DS%含量略低于对照组。结果提示HSPG可刺激HASMC的PG合成,其可能与血管壁修复及动脉壁脂质沉积有关。 相似文献
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野生大豆与栽培大豆rDNA ITS1区的研究 总被引:9,自引:0,他引:9
采用PCR 技术从野生大豆(Glycine soja)、半野生大豆(G.gracillis)、多年生野生大豆(G.tomentella、G.tabacina)和栽培大豆(G.m ax)的两个品种UNION、文丰7 中扩增和克隆了rDNA第一转录间隔区(ITS1)。其在G.m ax 基因组中的拷贝数约为2×103。序列分析表明G.soja、G.gracillis、G.m ax 中的G/C含量为61.40% ,而G.tabacina和G.tom entella的G/C含量分别为58.11% 和59.01% ,与绿豆G/C含量(59.81% )相近。G.tabacina的G/C含量是已知的植物中ITS1 最低的。最大同源性分析表明,大豆属植物ITS1 的同源程度很高,同其近缘属绿豆的同源性明显高于其它作物。同时分析了栽培、多年生和一年生野生大豆间的亲缘关系。另外还发现在已知的植物ITS1 序列中均含有GACCCGCGAA 及GCGCCAAGGAA 两个区段 相似文献
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通过微机对bcl-2RNA二级结构的分析,设计针对bcl-2片段5'CGCGACCCGGUCGCCAGGACCUCG3'的“锤头状”(Hammerhead)核酶(Ribozyme,RD)基因,平端连接于pGEM-3Zf(-)HincⅡ位点,克隆后经测序表明序列正确,bcl-2和Ribozyme基因经体外转录,50℃作用2h,从1656-1657(C-G)位之间切断bcl-2RNA片段. 相似文献
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观察了表皮生长因子(EGF),生长抑素(SS)对体外培养的人早孕绒毛膜促性腺激素(hCG)分泌及hCGβ-mRNA含量的影响。发现EGF可明显刺激绒毛分泌hCG,显著增加hCGβ-mRNA含量,生长抑素虽然对绒毛hCG分泌及hCG β-mRNA含量无明显影响,但可抑制EGF,GnRH刺激的hCG分泌及hCGβ-mRNA水平。提示EGF,SS在妊娠早期参与了hCG分泌的调节。 相似文献
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不同的下丘脑肽和神经递质对鲤鱼促性腺激素和生长激素分泌活动的影响 总被引:2,自引:0,他引:2
以1龄性腺发育中期鲤鱼为材料,采用腹腔(i.p)注射的方法,研究不同的下丘脑肽和神经递质对鲤鱼促性腺激素(GtH)和生长激素(GH)分泌的影响。结果表明:促甲状腺激素释放激素(TRH)、L-多巴(L-DOPA)、甲基睾酮(MT)、γ-氨基丁酸(GABA)、促黄体素释放激素类似物(LHRH-A)和三碘甲状腺原氨酸(T3)都能显著刺激GtH的分泌,但最大效应时间各不相同。TRH和LHRH-A能促进GH的分泌,L-DOPA、MT、GABA对血清GH水平没有明显影响;T3则对GH分泌有一定的抑制作用。这说明鲤鱼GtH和GH的分泌除了受各自的下丘脑释放因子和释放抑制因子的双重神经内分泌调控外,还受多种其它相同和不同调节因子的影响,也反映了鲤鱼GtH和GH分泌的神经内分泌调控的复杂性。 相似文献
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向日葵CMS育性恢复的研究 总被引:4,自引:1,他引:3
向日葵细胞质雄性不育(Cytoplasmicmalesterility,CMS)育性恢复的机理是非常复杂的。运用遗传学和分子生物学方法,分析了具代表性的4种不同细胞质类型的CMS育性被恢复的频率和20种向日葵自交系对19种CMS的恢复能力及个别CMS植株自发恢复的原因。实验结果表明,4种CMS品系育性被恢复的频率分别为58.8%.56.3%.11.8%和0%.20种自交系的恢复力为5.9-75.0%。部分CMS品系和大多数自交系含有恢复基因,恢复基因的数量及类型决定了CMS品系被恢复的程度及自交系的恢复能力。同时,提出并证实了线粒体不育基因变异是导致ARG1CMS植株自发恢复育性的主要原因。 相似文献
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目的:观察Beautifil氟化玻璃聚合体修复Ⅰ、Ⅲ、Ⅴ类洞的临床疗效.方法:用Beautifil修复108例患牙,6个月后复查,从脱落率、色泽稳定、界面染色、磨耗、继发龋、牙髓刺激性等方面来观察疗效.结果:Beautifil修复Ⅰ、Ⅲ、Ⅴ类洞型疗效良好.结论:Beautifil氟化玻璃聚合体作为一种新型牙色修复材料,具有多种优良理化性能,修复效果满意. 相似文献
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The development of genomic tools will enhance traditional tree breeding technologies leading to more certain and timely recovery
of the American chestnut, a keystone heritage tree of the eastern United States. Major efforts are being made in gene discovery,
genetic marker development, construction of a BAC-based physical map, and DNA transformation technology. A strategy of map-based
cloning, association genetics, and genetic engineering, combined with traditional and marker-assisted backcross breeding is
proposed for the long-term genetic restoration of this iconic tree species. 相似文献
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Taylor E.Shaw 《Plant Diversity》2019,(2):84-93
The Araucaria forest ecosystem in southern Brazil is highly threatened: less than one percent of the original forest remains, and what is left is a fragmented agro-mosaic of mostly early-to-late secondary forest patches among high-yield agriculture and timber monocultures. Forest restoration initiatives in this region aim to restore degraded areas, however the limited number of species used in restoration projects represents a missed opportunity for species-rich plantings. High diversity plantings represent a larger number of functional groups and provide a targeted conservation strategy for the high number of threatened species within this ecosystem. This study interviewed nurseries(Ns) and restoration practitioners(RPs) in Parana and Santa Catarina states to identify what species are being cultivated and planted, and what factors are driving the species selection process. An average of 20 species were reportedly used in restoration plantings, most of which are common, widespread species. Baseline data confirms that Ns and RPs have disproportionately low occurrences of threatened species in their inventories and plantings, supporting findings from previous research. Questionnaire responses reveal that opportunities for seed acquisition are an extremely important factor in order for nurseries to increase their diversity of cultivated species. Results also suggest that facilitating speciesrich plantings for restoration practitioners would only be feasible if it did not increase the time required to complete planting projects, as it would minimize their ability to keep costs low. This study proposes solutions for increasing the number of species used in restoration practicedsuch as developing a comprehensive species list, fostering knowledge-sharing between actors, creating seed sharing programs, and increasing coordination of planting projects. Long-term strategies involve complimenting traditional ex situ approaches with emerging inter-situ and quasi in situ conservation strategies which simultaneously provide long-term preservation of genetic diversity and increase seed production of target species. 相似文献
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调查观测广东韶关凡口铅锌矿宽叶香蒲(Typha latifolia)湿地的水生植物种类、生物多样性、群落结构及生物量,分析湿地基质的理化性质,探索湿地生态恢复的基本特征。研究结果表明:1) 以宽叶香蒲为优势种的湿地生态系统主要植物有98种,隶属44科,86属。次优势种有:芦苇(Phragmites communis)、茳芏(Cyperus malaccensis)。植物群落水平分布从均匀型向群集型分布格局转化,植物群落空间不均匀性增大。2) 随湿地系统的恢复演替进程,表现为土壤肥力(有机质,N,P,K)明 相似文献
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The ‘gardening concept’ for reef restoration focuses on coral colonies farming in mid-water nurseries before their transplantation onto denuded reef areas. Nurseries situated in a nutrient-enriched environment significantly curtail nursery time, but extend labor, as nursery construction and farmed corals must be frequently cleaned from competing fouling organisms. Mass farming of corals calls, therefore, for efficient and cheap maintenance methodologies, which we here tested by employing Aqua-guard M250, an anti-fouling agent used in the fish farming industry. We found that this anti-fouling paint, while reducing fouling organisms on nursery components during the crucial phase of coral ramets' development from nubbins and small fragments sizes to colony sizes suitable for transplantation, is not toxic to maricultured coral fragments that staged more than 2 cm away from the paint. Applying small quantities of such antifouling paint to coral nurseries, while restricting its use to nursery components that are not in direct contact with farmed coral material, reduces fouling coverage and cleaning procedures by 90%. 相似文献
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Astroturf seed traps for studying hydrochory 总被引:1,自引:0,他引:1
M. Wolters†‡ J. Geertsema E. R. Chang R. M. Veeneklaas P. D. Carey‡ J. P. Bakker 《Functional ecology》2004,18(1):141-147
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Abstract. This study focuses on the relationship between vegetation succession and soil seed bank composition on the Schiermonnikoog (The Netherlands) salt marsh over 100 yr. The importance of driftline material in seed dispersal and the relationship with succession is also investigated. The results indicate that the majority of species have a transient or short‐term seed persistent bank. Seeds of most species are able to float over the salt marsh and become concentrated in the driftline higher up the marsh. After plants have established a seed bank forms, which disappears when vegetation is replaced by later‐successional species. Exceptions are Spergularia mar‐itima, which is still present in the seed bank of late successional stages, and Juncus gerardi and Glaux maritima, which appear in the seed bank of early successional stages, but are absent in the vegetation. Based on the results of this study constraints and possibilities for salt‐marsh restoration by de‐embankment are discussed. 相似文献
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In the northeast US removal of exotic and invasive plant species is a common wetland restoration activity and the invasive common reed (Phragmites australis) is often the target of control efforts. We examined effects of reed removal on sediment nutrient pools and denitrification potential in a tidal freshwater marsh on the Connecticut River. In the first year after herbicide application and cutting of a reed stand, porewater ammonium concentrations in the removal area were about 4× higher relative to extant reed or cattail. Denitrification potentials were 50% lower than in a reference stand of reed. Denitrification activity had recovered by the second growing season after reed removal but porewater ammonium continued to accumulate. By the third growing season following reed removal, plant regrowth had occurred over approximately half the experimental plot and porewater ammonium had declined to pre-manipulation levels. Sediment organic content, moisture and porewater phosphate showed no significant response to reed removal over the four-year course of this study. Reed removal allowed regrowth of a more diverse plant community thereby achieving one of the goals of this restoration effort but patterns in ammonium accumulation and denitrification suggest a reduction in the capacity of this site to act as a sink for nitrogen. 相似文献