PEG介导的猴头菌遗传转化体系的建立

对猴头菌Hericium erinaceus原生质体制备的各种因素进行比较研究,结果表明,猴头菌原生质体制备的最佳体系为：液体培养5d的猴头菌丝,以0.6mol/L KCl作为稳渗剂,加入含1.0%纤维素酶+1.0%蜗牛酶+1.0%溶壁酶的复合酶,在30℃酶解猴头菌丝3h时,原生质体得率达到3.0×106个/mL。潮霉素敏感性测试表明,猴头菌在PDSA固体培养基上的潮霉素最低筛选浓度为60μg/mL。采用PEG介导的原生质体法,将质粒pBgGI-hph（含有灵芝gpd1-Gl启动子和潮霉素抗性基因hph）转化猴头菌原生质体,经潮霉素初步筛选以及PCR鉴定,表明有4株猴头菌拟转化子的基因组扩增出hph基因;转化子经过多次转接后进行Southern杂交验证,结果表明4个转化子的基因组中均稳定整合了hph抗性基因。     

贡蕉胚性悬浮细胞原生质体分离的研究

目的:研究不同方法对贡蕉胚性悬浮细胞原生质体分离的影响,筛选适合用于贡蕉胚性悬浮细胞原生质体分离的方案.方法:用不同的酶浓 度、酶组合及不同的酶解时间对贡蕉胚性悬浮细胞进行原生质体分离,并对不同继代时间的胚性悬浮细胞的原生质体产量和活力进行研究.结果:贡蕉胚性悬浮细胞 在酶组合为3.5%纤维素酶R-10、1%离析酶R-10和0.15%果胶酶Y-23的酶溶液中,酶解8h可获 得高产量的原生质体,采用继代7d的贡蕉胚性悬浮细胞进行原生质体分离时获得的原生质体产量最高,达到1.2×107个/mL PCV ECS,原生质体活力达到85%以上.结论: 合适的酶组合、酶浓度和酶解时间有利于贡蕉胚性悬浮细胞的原生质体分离,继代7d 后的贡蕉胚性悬浮细胞最适合用于原生质体分离.     

轮梗霉原生质体的制备*

本文比较了酶浓度、菌龄、渗透压稳定剂以及酶解温度和时间等因素对轮梗霉原生质体得率的影响。结果基本获得了制备原生质体的适宜条件:用0.6mol/L甘露醇稳渗剂配制成的4%纤维素酶和0.5%蜗牛酶混合酶,35℃酶解培养了30h的菌丝1.0h,即可得到较高产量的原生质体。对该原生质体进行了再生实验,其再生率约为23.8%。     

黄绿木霉原生质体诱变育种研究

利用正交实验方法研究了影响黄绿木霉(Trichoderma aureoviride)原生质体形成的因素,并利用紫外线、硫酸二乙酯、氯化锂几种因素复合诱变原生质体筛选高产纤维素酶菌株。影响原生质体形成的因子顺序是酶系统>菌龄>酶解时间>酶解温度,原生质体形成的最佳条件是0.5%蜗牛酶 0.5%溶菌酶 1.0%纤维素酶,菌龄为18h,酶解时间为3.0h,酶解温度为32℃;在该条件下原生质体产量可达到4.25×106个mL-1。Ca2 和PEG对提高原生质体再生率的作用明显;复合诱变后得到酶活显著提高、遗传性能稳定的诱变株T-14,其EG酶活与BG酶活分别提高了58.43%、44.48%。     

茶树叶肉原生质体的分离与纯化

以茶树幼苗叶片为材料,分析了甘露醇浓度、不同酶液组合、酶解时间等因素对叶肉原生质体分离及2种高密度分离液对原生质体纯化的影响。结果表明,叶片在含0.6 mol/L的甘露醇、1.5%的纤维素酶和2.5%的离析酶的酶解液中黑暗酶解16~18 h,叶肉原生质体的分离效果最好。此外,研究发现原生质体在10%的甘露醇与25%的碘克沙醇界面处聚集形成了一条带。     

黄曲霉菌原生质体的制备和再生技术优化

黄曲霉菌的遗传转化是研究黄曲霉菌致病相关功能基因的前提和基础,而原生质体是研究和建立真菌遗传转化系统的重要工具。本文分别以黄曲霉孢子和菌丝为材料,研究不同条件下黄曲霉原生质体的形成和再生,结果表明,黄曲霉孢子在酶液浓度为纤维素酶∶蜗牛酶∶溶壁酶=1.5%∶1.5%∶1.5%,30℃酶解3 h,原生质体制备率高达97.3%,再生率达89.2%;黄曲霉菌丝在菌龄为42 h,酶液浓度为纤维素酶∶蜗牛酶∶溶壁酶=1.5%∶1.5%∶1.5%,30℃酶解1 h,可获得最高原生质体产量为2.0×10^6个/m L,再生培养基中以1 mol/L蔗糖作为渗透压稳定剂时,原生质体再生率达5.5%。故本实验条件下,黄曲霉孢子原生质体的形成和再生优于菌丝。     

虎杖原生质体分离纯化及电融合初步研究

以野生虎杖根状茎芽为外植体诱导虎杖愈伤组织,选取生长状况良好的愈伤组织作为原生质体分离材料,通过L16（44）正交试验对虎杖原生质体分离条件进行优化.结果表明：1.4%纤维素酶R-10,0.1%果胶酶,17%甘露醇的酶液,酶解时间7h,虎杖原生质体分离效果最好.在80r/min振荡分离后虎杖原生质体得率为46.2%.以800r/min的离心速度纯化,纯化的原生质体得率为43.8%,其中原生质体的成活率为75%.通过对虎杖原生质体进行融合,原生质体的融合率为20.2%.     

虎仗原生质体分离纯化及电融合初步研究

以野生虎杖根状茎芽为外植体诱导虎杖愈伤组织,选取生长状况良好的愈伤组织作为原生质体分离材料,通过L16(44)正交试验对虎杖原生质体分离条件进行优化.结果表明:1.4%纤维素酶R-10,0.1%果胶酶,17%甘露醇的酶液,酶解时间7h,虎杖原生质体分离效果最好.在80r/min振荡分离后虎杖原生质体得率为46.2%.以800r/min的离心速度纯化,纯化的原生质体得率为43.8%,其中原生质体的成活率为75%.通过对虎杖原生质体进行融合,原生质体的融合率为20.2%.     

拟南芥叶肉原生质体分离条件的优化研究

以野生型拟南芥(Arabidopsis thaliana,ecotype Columbia)无菌苗为材料,研究了叶肉原生质体分离过程中的预处理条件、酶解方式、酶解温度和离心力大小等因素对产量和活力的影响.结果表明,酶解方式和酶解温度对原生质体产量影响显著,28℃静置酶解14 h能够将原生质体产量提高6.32倍.低温预处理和离心力大小对原生质体活力影响显著,4℃低温预处理24 h能够将原生质体活力提高55%.适宜拟南芥原生质体叶肉细胞分离的最佳条件为:4℃低温预处理24 h,28℃静置酶解14 h,600 r·min-1离心3次,每次10 min,得到的原生质体产量为2.91×106个·g-1,活力为84.03%.     

丹参悬浮培养细胞原生质体的制备和活力检测

对丹参悬浮培养细胞原生质体制备条件进行了研究,并利用FDA染色和钙离子荧光探针Fluo-3/AM装载对制备得到的原生质体的活力和功能进行了检测。丹参悬浮培养细胞原生质体的制备条件为:悬浮培养细胞酶解的适宜酶液组合为纤维素酶1.5%、果胶酶0.3%和离析酶0.5%;适宜的甘露醇浓度为0.4 mol/L;酶解时间为12 h;在600 r/min转速下离心5 min收集,纯化得到原生质体,其产量为1.1×106/g FW,FDA检测显示其活力为95%以上,荧光探针Fluo-3/AM可成功装载到原生质体中。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.