Cytosine
(Synonyms: 胞嘧啶) 目录号 : GC33594A pyrimidine base
Cas No.:71-30-7
Sample solution is provided at 25 µL, 10mM.
Quality Control & SDS
- View current batch:
- Purity: >99.50%
- COA (Certificate Of Analysis)
- SDS (Safety Data Sheet)
- Datasheet
Cytosine is a pyrimidine base.1 It forms complementary base pairs with the purine guanine in DNA and RNA and is a precursor of uracil . Methylation of cytosine is a key epigenetic mark that plays a role in gene regulation.2
1.Berg, J.M., Tymoczko, J.L., and Stryer, L.Nucleotide biosynthesisBiochemistry(2002) 2.Breiling, A., and Lyko, F.Epigenetic regulatory functions of DNA modifications: 5-methylcytosine and beyondEpigenetics Chromatin824(2015)
Cas No. | 71-30-7 | SDF | |
别名 | 胞嘧啶 | ||
Canonical SMILES | O=C1NC=CC(N)=N1 | ||
分子式 | C4H5N3O | 分子量 | 111.1 |
溶解度 | DMSO: 16.67 mg/mL (150.05 mM) | 储存条件 | Store at 2-8°C, protect from light |
General tips | 请根据产品在不同溶剂中的溶解度选择合适的溶剂配制储备液;一旦配成溶液,请分装保存,避免反复冻融造成的产品失效。 储备液的保存方式和期限:-80°C 储存时,请在 6 个月内使用,-20°C 储存时,请在 1 个月内使用。 为了提高溶解度,请将管子加热至37℃,然后在超声波浴中震荡一段时间。 |
||
Shipping Condition | 评估样品解决方案:配备蓝冰进行发货。所有其他可用尺寸:配备RT,或根据请求配备蓝冰。 |
制备储备液 | |||
1 mg | 5 mg | 10 mg | |
1 mM | 9.0009 mL | 45.0045 mL | 90.009 mL |
5 mM | 1.8002 mL | 9.0009 mL | 18.0018 mL |
10 mM | 0.9001 mL | 4.5005 mL | 9.0009 mL |
第一步:请输入基本实验信息(考虑到实验过程中的损耗,建议多配一只动物的药量) | ||||||||||
给药剂量 | mg/kg | 动物平均体重 | g | 每只动物给药体积 | ul | 动物数量 | 只 | |||
第二步:请输入动物体内配方组成(配方适用于不溶于水的药物;不同批次药物配方比例不同,请联系GLPBIO为您提供正确的澄清溶液配方) | ||||||||||
% DMSO % % Tween 80 % saline | ||||||||||
计算重置 |
计算结果:
工作液浓度: mg/ml;
DMSO母液配制方法: mg 药物溶于 μL DMSO溶液(母液浓度 mg/mL,
体内配方配制方法:取 μL DMSO母液,加入 μL PEG300,混匀澄清后加入μL Tween 80,混匀澄清后加入 μL saline,混匀澄清。
1. 首先保证母液是澄清的;
2.
一定要按照顺序依次将溶剂加入,进行下一步操作之前必须保证上一步操作得到的是澄清的溶液,可采用涡旋、超声或水浴加热等物理方法助溶。
3. 以上所有助溶剂都可在 GlpBio 网站选购。
Cytosine methylation and DNA repair
Curr Top Microbiol Immunol 2006;301:283-315.PMID:16570853DOI:10.1007/3-540-31390-7_11.
Cytosine methylation is a common form of post-replicative DNA modification seen in both bacteria and eukaryotes. Modified cytosines have long been known to act as hotspots for mutations due to the high rate of spontaneous deamination of this base to thymine, resulting in a G/T mismatch. This will be fixed as a C-->T transition after replication if not repaired by the base excision repair (BER) pathway or specific repair enzymes dedicated to this purpose. This hypermutability has led to depletion of the target dinucleotide CpG outside of special CpG islands in mammals, which are normally unmethylated. We review the importance of C-->T transitions at non-island CpGs in human disease: When these occur in the germline, they are a common cause of inherited diseases such as epidermolysis bullosa and mucopolysaccharidosis, while in the soma they are frequently found in the genes for tumor suppressors such as p53 and the retinoblastoma protein, causing cancer. We also examine the specific repair enzymes involved, namely the endonuclease Vsr in Escherichia coli and two members of the uracil DNA glycosylase (UDG) superfamily in mammals, TDG and MBD4. Repair brings its own problems, since it will require remethylation of the replacement Cytosine, presumably coupling repair to methylation by either the maintenance methylase Dnmt1 or a de novo enzyme such as Dnmt3a. Uncoupling of methylation from repair may be one way to remove methylation from DNA. We also look at the possible role of specific Cytosine deaminases such as Aid and Apobec in accelerating deamination of methylcytosine and consequent DNA demethylation.
TET enzymes, TDG and the dynamics of DNA demethylation
Nature 2013 Oct 24;502(7472):472-9.PMID:24153300DOI:10.1038/nature12750.
DNA methylation has a profound impact on genome stability, transcription and development. Although enzymes that catalyse DNA methylation have been well characterized, those that are involved in methyl group removal have remained elusive, until recently. The transformative discovery that ten-eleven translocation (TET) family enzymes can oxidize 5-methylcytosine has greatly advanced our understanding of DNA demethylation. 5-Hydroxymethylcytosine is a key nexus in demethylation that can either be passively depleted through DNA replication or actively reverted to Cytosine through iterative oxidation and thymine DNA glycosylase (TDG)-mediated base excision repair. Methylation, oxidation and repair now offer a model for a complete cycle of dynamic Cytosine modification, with mounting evidence for its significance in the biological processes known to involve active demethylation.
Oxidized C5-methyl Cytosine bases in DNA: 5-Hydroxymethylcytosine; 5-formylcytosine; and 5-carboxycytosine
Free Radic Biol Med 2017 Jun;107:62-68.PMID:27890639DOI:10.1016/j.freeradbiomed.2016.11.038.
Recent reports suggest that the Tet enzyme family catalytically oxidize 5-methylcytosine in mammalian cells. The oxidation of 5-methylcytosine can result in three chemically distinct species - 5-hydroxymethylcytsine, 5-formylcytosine, and 5-carboxycytosine. While the base excision repair machinery processes 5-formylcytosine and 5-carboxycytosine rapidly, 5-hydroxymethylcytosine is stable under physiological conditions. As a stable modification 5-hydroxymethylcytosine has a broad range of functions, from stem cell pluriopotency to tumorigenesis. The subsequent oxidation products, 5-formylcytosine and 5-carboxycytosine, are suggested to be involved in an active DNA demethylation pathway. This review provides an overview of the biochemistry and biology of 5-methylcytosine oxidation products.
Antigen Retrieval for Immunostaining of Modified Cytosine Species
Methods Mol Biol 2021;2198:217-226.PMID:32822035DOI:10.1007/978-1-0716-0876-0_18.
Immunostaining (also called as immunofluorescence) is a fluorescence labeling method to stain one or more epitopes of interest on DNA and/or protein using specific antibodies. Cytosine modifications can be detected quantitatively by immunostaining. The protocol commonly includes sequential steps. These include fixation, permeabilization, antigen retrieval, blocking, incubation with primary and secondary antibodies, and visualization under the microscope followed by image-based intensity analysis of staining. Each step is important, but antigen retrieval is especially necessary for DNA epitopes such as Cytosine modifications as antibodies can access cytosines in DNA only once the DNA double-strand is denatured and DNA-packaging proteins have been removed. Hydrochloric acid is commonly used for this purpose. However, there are additional treatments with enzymes to enhance antigen retrieval and improve the detection by increasing staining intensity. This chapter describes current methodology for improving antigen retrieval for the staining of the Cytosine modifications 5'-methylcytosine (5meC), 5'-hydroxymethylcytosine (5hmC), 5'-formylcytosine (5fC), and 5'-carboxycytosine (5caC).
Global analysis of Cytosine and adenine DNA modifications across the tree of life
Elife 2022 Jul 28;11:e81002.PMID:35900202DOI:10.7554/eLife.81002.
Interpreting the function and metabolism of enzymatic DNA modifications requires both position-specific and global quantities. Sequencing-based techniques that deliver the former have become broadly accessible, but analytical methods for the global quantification of DNA modifications have thus far been applied mostly to individual problems. We established a mass spectrometric method for the sensitive and accurate quantification of multiple enzymatic DNA modifications. Then, we isolated DNA from 124 archean, bacterial, fungal, plant, and mammalian species, and several tissues and created a resource of global DNA modification quantities. Our dataset provides insights into the general nature of enzymatic DNA modifications, reveals unique biological cases, and provides complementary quantitative information to normalize and assess the accuracy of sequencing-based detection of DNA modifications. We report that only three of the studied DNA modifications, methylcytosine (5mdC), methyladenine (N6mdA) and hydroxymethylcytosine (5hmdC), were detected above a picomolar detection limit across species, and dominated in higher eukaryotes (5mdC), in bacteria (N6mdA), or the vertebrate central nervous systems (5hmdC). All three modifications were detected simultaneously in only one of the tested species, Raphanus sativus. In contrast, these modifications were either absent or detected only at trace quantities, across all yeasts and insect genomes studied. Further, we reveal interesting biological cases. For instance, in Allium cepa, Helianthus annuus, or Andropogon gerardi, more than 35% of cytosines were methylated. Additionally, next to the mammlian CNS, 5hmdC was also detected in plants like Lepidium sativum and was found on 8% of cytosines in the Garra barreimiae brain samples. Thus, identifying unexpected levels of DNA modifications in several wild species, our resource underscores the need to address biological diversity for studying DNA modifications.