用T-DNA插入突变的方法获得稻瘟病菌致病突变体

利用农杆菌介导转化的方法共得到1 114个稻瘟病菌转化子,经感病大麦和水稻离体叶片接种鉴定获得3个致病缺陷或下降突变体:A1-134、A1-452、和A2-1-8,其中A1-134和A1-452的致病性下降,而A2-1-8突变体的致病性丧失.对这些突变体的分生孢子形态、产孢、附着胞形成等表型分析的结果发现,A1-134突变体的产孢量显著下降,仅为野生菌株Guy11的7.7,分生孢子为圆球形,无隔膜或只有一个隔膜;A1-452产孢量明显增多,为Guy11的22倍;A2-1-8的分生孢子为长针形,产孢量略有下降;A1-134和A1-452在疏水表面的附着胞形成率与Guy11相近,而A2-1-8则不能形成附着胞.研究结果为进一步鉴定和分离这些突变体的T-DNA标记基因奠定了基础.     

Arabidopsis thaliana and Plant Molecular Genetics

Arabidopsis thaliana is a small flowering plant with various properties that make it an excellent organism for experiments in molecular genetics. These properties include having a small nuclear genome, a near absence of dispersed repetitive DNA, and a generation time of 4 to 5 weeks. In addition, mutations that affect hormone synthesis and response, many different enzyme activities, and numerous developmental processes have been identified and characterized.     

拟南芥开花相关的分子调控机制的研究

植物开花是基因与环境因子协同调节的复杂过程。对于拟南芥开花的调控过程,主要分为温度途径、光周期途径、自主途径、春化途径、年龄途径和赤霉素途径六个主要途径,然后SOC1和FT等开花途径整合因子感知来自不同途径的信号,并且将信号传递给花分生组织决定基因LFY和AP1,从而完成对开花时间的精准把握和控制,最终完成拟南芥开花的整个形态建成过程。该研究就这六条主要调控机制如何调节拟南芥开花进程的机理做进一步的介绍和阐述。     

拟南芥营养突变体的初步筛选

采用发芽和幼苗试验探索了筛选拟南芥抗某些抑制性物质的适宜浓度,其中2,4-D,6－BA,NaCl,AI3 ,Cu2 ,CrO4或2,4-DNP分别是10μmol．L-1,5μmol．L-1,2O0μmol．L-1,500μmol．L-1,20μmol．L-1,500μmol．L-1和18μmol．L-1。在该浓度下对经化学诱变处理获得的M2种子进行了发芽法筛选,得到了在高浓度抑制物存在时表现不同的可能突变株。     

Transformation of Arabidopsis thaliana with Agrobacterium tumefaciens

Transformed Arabidopsis thaliana plants have been produced by a modified leaf disk transformation-regeneration method. Leaf pieces from sterilely grown plants were precultured for 2 days and inoculated with an Agrobacterium tumefaciens strain containing an avirulent Ti (tumor-inducing) plasmid with a chimeric gene encoding hygromycin resistance. After cocultivation for 2 days, the leaf pieces were placed on a medium that selects for hygromycin resistance. Shoots regenerated within 3 months and were excised, rooted, and transferred to soil. Transformation was confirmed by opine production, hygromycin resistance, and DNA blot hybridization of both primary transformants and progeny. This process for producing transgenic Arabidopsis plants should enhance the usefulness of the species for experimental biology.     

The evolution of selfing in Arabidopsis thaliana

Unlike most of its close relatives, Arabidopsis thaliana is capable of self-pollination. In other members of the mustard family, outcrossing is ensured by the complex self-incompatibility (S) locus,which harbors multiple diverged specificity haplotypes that effectively prevent selfing. We investigated the role of the S locus in the evolution of and transition to selfing in A. thaliana. We found that the S locus of A. thaliana harbored considerable diversity, which is an apparent remnant of polymorphism in the outcrossing ancestor. Thus, the fixation of a single inactivated S-locus allele cannot have been a key step in the transition to selfing. An analysis of the genome-wide pattern of linkage disequilibrium suggests that selfing most likely evolved roughly a million years ago or more.     

Tryptophan-Requiring Mutants of the Plant Arabidopsis thaliana

Although amino acid auxotrophs are among the most frequently isolated mutations in microorganisms, no mutants that require amino acids have been isolated at the whole plant level. Tryptophan-requiring mutants of the cruciferous plant Arabidopsis thaliana have now been isolated by selecting for resistance to 5-methylanthranilic acid. The tryptophan requirement of one mutant, trpl-1, results from a defect in the second step of the tryptophan pathway catalyzed by anthranilate phosphoribosyl transferase. Mutant trpl-1 plants are highly fluorescent and aromatic because they accumulate anthranilic acid and anthranilate beta-glucoside. Plants homozygous for the trpl-1 mutation exhibit a syndrome of morphological defects suggestive of a defect in the biosynthesis, metabolism, or localization of a tryptophan derivative such as auxin. All of these morphological phenotypes cosegregate with the tryptophan requirement as a simple Mendelian recessive trait.     

Genome-wide Analysis of Ovate Family Proteins in Arabidopsis

Arabidopsis thaliana ovate family proteins (AtOFPs) is a newly found plant-specific protein family interacting with TALE (3-aa loop extension homeodomain proteins) homeodomain proteins in Arabidopsis. ...     

AtNUDT8过量表达的拟南芥转基因植株

从拟南芥基因组中克隆AtNUDT8,并与pCHF3相连构建了植物表达载体pCHFN8,采用农杆菌GV3101介导的渗透法转化野生型拟南芥,通过卡那霉素筛选获得了一批经Northern blot检测证实的过量表达AtNUDT8的转基因拟南芥植株。     

Quercetin Promotes Auxin Transport in Arabidopsis thaliana

Study on the role of quercentin in polar auxin transportation. Arabidopsis was cultured on medium supplemented with quercetin to observe the growth of hypocotyls, 14C-IAA transport assays were conducted to measure the auxin transport activity. The results showed that Arabidopsis mutant auxl which had been deficient in auxin influx transportion obviously recovered the ability after cultured on the medium with quercetin. The polar auxin transport was promoted by the addition of quercetin. These results indicated that quereetin could promote polar auxin transport in vivo.     

槲皮素促进拟南芥生长素极性运输的研究

用含有外源槲皮素的培养基种植拟南芥，探讨槲皮素对拟南芥生长素极性运输的影响。     

槲皮素促进拟南芥生长素极性运输的研究(英文)

Study on the role of quercentin in polar auxin transportation. Arabidopsis was cultured on medium supplemented with quercetin to observe the growth of hypocotyls,14C-IAA transport assays were conducted to measure the auxin transport activity. The results showed that Arabidopsis mutant aux1 which had been deficient in auxin influx transportion obviously recovered the ability after cultured on the medium with quercetin. The polar auxin transport was promoted by the addition of quercetin. These results indicated that quercetin could promote polar auxin transport in vivo.     

Quercetin Promotes Auxin Transport in Arabidopsis thaliana

Study on the role of quercentin in polar auxin transportation. Arabidopsis was cultured on medium supplemented with quercetin to observe the growth of hypocotyls,14C-IAA transport assays were conducted to measure the auxin transport activity. The results showed that Arabidopsis mutant aux1 which had been deficient in auxin influx transportion obviously recovered the ability after cultured on the medium with quercetin. The polar auxin transport was promoted by the addition of quercetin. These results indicated that quercetin could promote polar auxin transport in vivo.     

禾谷镰刀菌侵染拟南芥的研究

本研究采用禾谷镰刀菌侵染拟南芥,结果表明,在拟南芥开花初期,采用分生孢子悬浮液喷雾接种,能够引起花组织和角果产生病变,菌丝进一步扩展到整个植株中,最终引起植株坏死。用组织染色及特异引物进行PCR扩增,证实接种菌已侵入植物组织。说明拟南芥可用来进行禾谷镰刀菌侵染过程的相关分析,也可为筛选抗赤霉病的基因提供新思路。     

A map of local adaptation in Arabidopsis thaliana

Local adaptation is critical for species persistence in the face of rapid environmental change, but its genetic basis is not well understood. Growing the model plant Arabidopsis thaliana in field experiments in four sites across the species' native range, we identified candidate loci for local adaptation from a genome-wide association study of lifetime fitness in geographically diverse accessions. Fitness-associated loci exhibited both geographic and climatic signatures of local adaptation. Relative to genomic controls, high-fitness alleles were generally distributed closer to the site where they increased fitness, occupying specific and distinct climate spaces. Independent loci with different molecular functions contributed most strongly to fitness variation in each site. Independent local adaptation by distinct genetic mechanisms may facilitate a flexible evolutionary response to changing environment across a species range.     

超高效液相色谱法测定拟南芥芥子油苷

将已有的拟南芥芥子油苷高效液相色谱(HPLC)检测方法转换为超高效液相色谱(UPLC)方法,通过条件优化改进,建立拟南芥芥子油苷UPLC检测方法。该方法采用Waters ACQUITY UPLC HSS T3色谱柱(50 mm×2.1 mm,1.8μm),以超纯水和甲醇为流动相进行梯度洗脱,流速为0.40 mL·min-1,检测波长229 nm,进样量5μL,内标为苯甲基芥子油苷。利用此方法测得样品的日内和日间精密度均小于9.62%,用此方法与HPLC法测定生长10周的拟南芥莲座叶中各种芥子油苷组分含量一致。方法简单、快速、准确,适用于拟南芥芥子油苷组分及含量的分析。     

拟南芥室内繁种技术研究

拟南芥种子小 ,幼苗脆弱 ,且国内许多实验室的条件又较简陋 ,因此 ,结合当地的实验条件和气候特点掌握拟南芥的繁种技术非常重要。华南农业大学植物营养遗传研究室从美国引进 4种拟南芥突变体繁种并获得成功 ,现将一些室内繁种的经验和体会报道如下。1　材料与方法实验材料为拟南芥野生型Ｃｏｌｕｍｂｉａ的 4种突变体 ,选用了 3种培养方法进行拟南芥繁育技术试验。包括移栽法、蛭石法和 5∶5法。 (1)移栽法 :将种子消毒后 ,播于无菌培养基上 ,置于 4℃冰箱内春化 4～ 5ｄ ,之后转入光照培养。培养皿垂直放置 ,培养 4周后 ,将小苗移栽到营养…