相关实验视频
Updated: Jun 4, 2025

10:25
Using the E1A Minigene Tool to Study mRNA Splicing Changes
Published on: April 22, 2021
4.8K
机械洞察力转化后的α-基托-β-氨基酸形成由一个激进的S-腺甲胺拼接asease
Anna L Vagstad1, Edgars Lakis1, Katja-Sophia Csizi2
1Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, 8093, Zurich, Switzerland.
Angewandte Chemie (International ed. in English)
|December 17, 2024
概括
激进的S-adenosyl metionin酶通过切除 tyramine 来产生氨基酸来进行一种罕见的蛋白质修饰. 这项研究揭示了这种由基因介导的生物转化机制,这对于生物活性化物至关重要.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 自然产品 化学 化学
背景情况:
- 激进的S-adenosyl metionin (SAM) 酶催化各种翻译后修饰.
- 一个独特的修改涉及通过提拉胺切除安装α-keto-β-氨基酸残留物,这对于spliceotide生物活性至关重要.
研究的目的:
- 阐明由拼接酶介导的非正规蛋白质拼接的机制.
- 为了研究模型拼接酶PcpXY.的体外活性.
主要方法:
- 在体外测定使用PcpXY拼接酶.
- 反应分流和副产品的识别.
- 乳标签研究.
- 密度函数理论 (DFT) 能量计算.
主要成果:
- 支持了一种涉及在氨酸Cα处初始提取的机制.
- 确定了作为副产品的4-基甲的激素形成和释放.
- 这项研究揭示了前所未有的激素介导生物转化.
结论:
- 这些发现澄清了由PcpXY.spliceotide成熟的机制.
- 这种基因介导的过程产生了在治疗中发现的胺基药.
相关概念视频
RNA Splicing
56.0K
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
56.0K
RNA Editing
8.9K
RNA editing is a post-transcriptional modification where a precursor mRNA (pre-mRNA) nucleotide sequence is changed by base insertion, deletion, or modification. The extent of RNA editing varies from a few hundred bases, in mitochondrial DNA of trypanosomes, to a just single base, in nuclear genes of mammals. Even a single base change in the pre-mRNA can convert a codon for one amino acid into the codon for another amino acid or a stop codon. This type of re-coding can significantly affect the...
8.9K
Translocation of Proteins into the Mitochondria
3.0K
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
3.0K
Leaky Scanning
5.1K
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R...
5.1K
Improving Translational Accuracy
8.8K
Base complementarity between the three base pairs of mRNA codon and the tRNA anticodon is not a failsafe mechanism. Inaccuracies can range from a single mismatch to no correct base pairing at all. The free energy difference between the correct and nearly correct base pairs can be as small as 3 kcal/ mol. With complementarity being the only proofreading step, the estimated error frequency would be one wrong amino acid in every 100 amino acids incorporated. However, error frequencies observed in...
8.8K
tRNA Activation
18.9K
Aminoacyl-tRNA synthetases are present in both eukaryotes and bacteria. Though eukaryotes have 20 different aminoacyl-tRNA synthetases to couple to 20 amino acids, many bacteria do not have genes for all of these aminoacyl-tRNA synthetases. Despite this, they still use all 20 amino acids to synthesize their proteins. For instance, some bacteria do not have the gene encoding the enzyme that couples glutamine with its partner tRNA. In these organisms, one enzyme adds glutamic acid to all of the...
18.9K

