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1.
KCN和NaN3预处理对烟草愈伤组织抗氰呼吸的影响   总被引:3,自引:0,他引:3  
用0.5 m m ol/L KCN 或0.01 m m ol/L NaN3 预处理继代培养25 d 的“甘肃黄花烟草”(Nicotiana rustica L. cv. Gansu yellow flow er)愈伤组织对其呼吸作用有明显的影响。KCN 和NaN3 预处理12 h 可分别使愈伤组织的总呼吸速率下降12% 和17% ,细胞色素途径的实际运行量分别下降22% 和28% ;抗氰交替途径在最大容量(Valt)基本不变的情况下,实际运行量(ρ·Valt)不但未随总呼吸速率和细胞色素途径运行量的下降而降低,反而还略有上升。结果导致细胞色素途径对总呼吸的贡献下降而抗氰交替途径对总呼吸的贡献上升。KCN 预处理24 h,细胞色素途径的实际运行量虽略有回升,但仍低于对照;NaN3 预处理24 h 则使细胞色素途径运行继续下降而交替途径运行持续上升。上述结果表明,在继代培养的烟草愈伤组织中,当细胞色素主路途径被部分抑制后交替途径的电子流量明显加强,从而起着一种补偿作用  相似文献   

2.
实验结果表明:烟划愈伤组织在生长和衰老期间,总呼吸速率(Vt)分别在11d和19d出现2次呼吸跃升;细胞色素途径的运行(ρ'Vcyt)与Vt的变化几乎一致,表明细胞色素途径仍组织主要的电子传递途径;交替途径容量(Valt)及其与Vt的比值(Valt/Vt):在15d前不断上升,而在15-19d之间处于稳定水平后下降。交替途径运行(ρValt)及其对Vt的贡献(ρValt/Vt)却与Valt变化趋势  相似文献   

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微量元素锗对四种微藻光合色素的影响   总被引:3,自引:0,他引:3  
采用溶液培养方法,以锗作为胁迫因子,研究了锗对4种微藻“钝顶螺旋藻(Spirulina platensis)、盐生杜氏藻(Dunaliella salina)、淇江叉鞭金藻(Dicrateria zhanjiangensis)和微绿藻(Nannochloropsis.sp)光合色素的影响。实验结果表明,经10mg/dm^3锗处理后,四种藻类细胞中的光合色素都发生了较大变化,有些色素发生明显的增加或  相似文献   

4.
低温对不同耐冷力的黄瓜幼苗呼吸代谢的影响   总被引:6,自引:0,他引:6  
两个品种的黄瓜幼苗,经2℃低温处理之后,子叶的呼吸代谢活性均有不同程度的增强,无论是呼吸强度的变化,或是底物氧化途径和电子传递途径的活性变化,均显示出低温有促进作用。耐冷力较强的粵早3号增加的幅度略大于耐冷力较差的全青。 黄瓜幼苗子叶呼吸代谢途径在总呼吸中的分配比例的变化是:在28℃的条件下,随苗龄的增长,子叶的底物氧化途径逐步转变为以EMP途径为主,电子传递途径则以交替途径为主。2℃的低温处理使底物氧化途径加速或增大,转向以EMP途径为主,而电子传递途径则从原来的交替途径为主变为以细胞色素途径为主。耐冷力不同的品种之间的反应,主要表现在呼吸代谢途径变化的趋势上有一定的差异。在1星期低温的范围内,随着低温处理时间的延长耐冷力较强的粵早3号,其各途径在分配比例上保持在平稳状态。  相似文献   

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利用番茄(Lycopersicum esculentum Mill.)县浮培养细胞为材料,以^32P标记的寡核苷酸(40bp)为探针检测了细胞外钙调素对番茄细胞rbcS-3A及rbcS-3C基因表达的影响。当向暗中培养的番茄悬浮细胞(第7天)中加入外源纯化钙调素(10^-7mol/L)并处理24h后,rbcB-3A基因的表达明显增加,而相同深度的S-100蛋白和BSA则没有作用。加入外源钙调素(1  相似文献   

6.
小麦幼苗叶片抗氰呼吸对轻度水分胁迫的响应   总被引:6,自引:1,他引:5  
小麦幼苗经-0.5MPa聚乙二醇(PEG-6000)溶液暗中渗透迫0、6、12、18、24、30、36、42、48h,叶片的总呼吸速率(Vt)呈现先上升后降低的趋势,交替途径呼吸也表现出相同的变化模式。水分胁迫初期(0-12h),交替途径容量(Valt)、实际运行活性(ρValt)及运行系数(ρ值)均上升,此后(18-48h)逐渐下降,水分胁迫也影响了呼吸电子流在2条呼吸途径中的分配比例,胁迫初期的0-12h内,流经交替途径的电子流增多,而流向细胞色素主路的电子流减少,但随着胁迫时间的延长,交替途径的贡献降低,而细胞色素主路的贡献增加,说明小麦叶片的抗氰呼吸在水分胁迫初期被诱导增加,而随着胁迫进行的延长又表现为下降。  相似文献   

7.
孔庆鹏  黄顺友 《遗传》2000,22(6):379-384
本研究测定了长臂Ba属(Mystacoleucus Guenther)中的3个种:月斑长臂Ba(M.chilopterus Fowler)、长臂Ba〔M.marginatus(Cuvrier et Valenciennse)〕和细尾长臂Ba(M.lepturus Huang)共22个个体的线粒体细胞色素b部分基因片段,其序列为408bp,并选用Pang Pi(Rhodeus sinensis Cu  相似文献   

8.
石防风原生质体遗传转化及抗除草剂植株的再生   总被引:2,自引:0,他引:2  
以石防风(Peucedanumterebinthaceum(Fisch.)Fisch.exTurcz.)叶柄愈伤组织为材料建立以致密细胞团为主的悬浮培养物,用酶解法获得原生质体。用PEG法将拟南芥菜(Arabidopsisthaliana(L.)Heynh.)抗除草剂基因导入原生质体后进行液体浅层培养。转化细胞经除草剂chlorsulfuron筛选,通过胚状体途径产生抗性小植株。转化处理106个原生质体,以加入40~50μg/mL质粒DNA,PEG终浓度为10%,于1mL转化介质中,26℃黑暗下处理20min的效果最好。ctDNA的加入对转化结果无明显影响。分子杂交试验表明,突变的als基因已整合进转化植株的基因组中。转基因植株的细胞在脱分化过程中仍具有抗chlorsulfuron的能力;移栽成活的转基因小苗仍表现出抗除草剂特性,而未转化的植株在低浓度除草剂下即逐渐死亡。表明转入的als基因在石防风细胞内能够稳定表达。  相似文献   

9.
真菌诱导子对青蒿发根细胞生长和青蒿素积累的影响   总被引:8,自引:0,他引:8  
3种真菌诱导子(大菌丽花轮枝孢(Verticillium dahiae Kleb.)、葡枝根霉(Rhizopus stolonifer(Ehrenb.exFr.)Vuill)和束状刺盘孢(Colletorichum dematium(Pers.)Grove)处理青蒿(Artemisia annuaL.)的发根,均能促进发根中青蒿素的积累,其中以大丽花轮枝孢的诱导效果最好;对细胞生长均没有明显影响,  相似文献   

10.
辛越勇  郁飞 《Acta Botanica Sinica》2000,42(12):1225-1230
采用一种快速简捷的方法从菠菜(Spinacia oleracea L.)和水稻(Oryza sativa L.)中分离纯化了光系统Ⅱ反应中心内的细胞色素b-559,并且研究了其低温可见光区荧光光谱、室温紫外区荧光光谱、吸收光谱以及电泳特性。该方法的主要特点:1.以放氧核心复合物为起始材料以避免其他细胞色素的干扰;2.选用DEAE-Sephacel为层析介质,用等度洗脱除去杂蛋白和叶绿素;3.用同一  相似文献   

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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.  相似文献   

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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.  相似文献   

17.
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.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
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  相似文献   

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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.  相似文献   

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