结构与功能

实验简介植物的基因组大小及 DNA 倍性和植物的品系、性状及营养和药用价值有密切联系。检测植物的基因组大小和 DNA 倍性在植物的鉴定、杂交育种等领域有重要意义。流式细胞仪可在半小时内完成从样本制备染色、植物基因组大小和 DNA 倍性测定全过程，以其方便快捷得到广泛应用。CytoFLEX 流式细胞仪具有优异的荧光分辨能力，可轻易区分不同大小的基因组，多达 10 的 7 次方线性检测范围，可更好地检测自然界或育种过程中广泛存在的多倍体现象。材料与方法▶ 试剂▶ ...

荧光素酶自然界中的荧光素酶：是自然界中能够产生荧光的酶的系统，如发光真菌，发光海星，发光鱼，发光节虫，发光甲虫等。萤火虫荧光素酶：目前常用的萤火虫荧光素酶来源于北美萤火虫（Photinus pyralis）,是一个61KDa的单体酶，无需表达后修饰，直接具有完全酶活性，反应需要底物荧光素以及ATP、氧气、镁离子等。海肾荧光素酶：来源于海肾（Renilla reniformis），是一个36KDa的单体酶，表达后无需修饰，即可具 ...

一、实验设计的意义实验设计是科学研究计划内关于研究方法与步骤的一项内容。在医学科研工作中，无论实验室研究、临床疗效观察或现场调查，在制订研究计划时，都应根据实验的目的和条例，结合统计学的要求，针对实验的全过程，认真考虑实验设计问题。一个周密而完善的实验设计，能合理地安排各种实验因素，严格地控制实验误差，从而用较少的人力、物力和时间，最大限度地获得丰富而可靠的资料。反之，如果实验设计存在着缺点，就可能造成不应有的浪费 ...

Fluorescent-based technologies offer opportunities for developing new assays for detection, quantification, and characterization of viral isolates. According to the intrinsic characteristics of fluorescent-based tools (high specificity, sensitivity, and relia ...

miRNAs have emerged as key regulators of gene expression in both plants and animals. These small (generally 21–22 nt) RNA molecules, originated from primary “hairpin” transcripts, can induce translational suppression or direct mRNA cleavage. Similar to regular mRNAs, the expression of ...

Non-invasive microelectrode ion flux measuring (the MIFE system) allows concurrent quantification of net fluxes of several ions with high spatial (several μm) and temporal (ca 5 s) resolution. Over the last 10 years, the MIFE system has been widely used to study various aspects of salt stress sig ...

Nearly all signal transduction pathways lead to regulation of gene expression by controlling specific transcription factors (TFs). Chromatin immunoprecipitation (ChIP) is a powerful method for studying TF–DNA interactions in vivo. To identify all binding sites of a TF in the genome, t ...

Chimeric REpressor gene Silencing Technology (CRES-T) is a useful tool for functional analysis of plant transcription factors. In this system, a chimeric repressor that is produced by fusion of a transcription factor to the plant-specific EAR-motif repression domain (SRDX) suppres ...

Chloroplasts are metabolically important organelles that perform many essential functions within plant cells. The chloroplasts can be subdivided into six distinct sub-compartments to which a protein may be ultimately targeted. These sub-compartments are defined as the outer e ...

Soil salinity reduces the ability of plants to take up water, and this quickly causes reductions in the rate of cell expansion in growing tissues. The slower formation of photosynthetic leaf area in turn reduces the flow of assimilates to the meristematic and growing tissues of the plant. Later, salt ...

Genome-wide quantitative profiling of chromatin modifications is a critical experimental approach to study epigenetic and transcriptional control mechanisms. Since first being reported in 2007, chromatin immunoprecipitation followed by high-throughput sequenci ...

Histone modifications play an essential role in chromatin-associated processes including gene regulation and epigenetic inheritance. It is therefore very important to quantitatively analyze histone modifications at both the single gene and whole genome level. Here, we descr ...

Methylation-sensitive amplified polymorphism (MSAP) is a technique developed for assessing the extent and pattern of cytosine methylation and has been applied to genomes of several species (Arabidopsis, grape, maize, tomato, and pepper). The technique relies on the use of isoschizo ...

The quantitative real-time polymerase chain reaction is used to simultaneously amplify and quantify a targeted DNA molecule. It can be used to determine exact copy number of a molecule within a sample and/or to compare the quantity of a molecule between samples. When combined with reverse tran ...

Molecular techniques have created the opportunity for great advances in plant mutation genetics and the science of mutation breeding. The powerful targeted induced local lesions in genomes (TILLING) technique has introduced the possibility of reverse genetics—the ability to sc ...

The polymerase chain reaction (PCR) converts very low quantities of DNA into very high quantities and is the foundation of many specialized techniques of molecular biology. PCR utilizes components of the cellular machinery of mitotic cell division in vitro which respond predictably to u ...

Bacterial artificial chromosome (BAC) libraries are extremely valuable large-insert DNA libraries for physical mapping, positional cloning, comparative genomic analysis, complete genome sequencing, and evolutionary studies. Due to their stability and relative simpl ...

The construction of full-length cDNA libraries allows researchers to study gene expression and protein interactions and undertake gene discovery. Recent improvements allow the construction of high-quality cDNA libraries, with small amounts of mRNA. In parallel, these improve ...

Cereal grains, as storage tissues of the plant, contain high amounts of starch. Purification of RNA from plant tissue especially from seed tissue can be challenging due to this high starch content. Starch coprecipitates with RNA in the presence of isopropanol or ethanol and can interfere with the ...

Ribonucleic acid (RNA) extraction is the necessary first step in many protocols, primarily to investigate genes and gene expression. RNA comes in a variety of forms: total RNA, ribosomal RNA, messenger RNA (mRNA), and small interfering RNA (siRNA) to name a few. In some instances, total RNA is all that is ...