发展中的小鼠大脑的分子结构
Gioele La Manno1,2, Kimberly Siletti3, Alessandro Furlan3,4
1Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden. gioele.lamanno@epfl.ch.
Nature
|July 29, 2021
概括
研究人员创建了一个完整的小鼠胚胎大脑分子地图,识别了近800个细胞状态,并绘制了基因表达图,以了解从胃化到出生的大脑发育.
科学领域:
- 神经科学
- 发育生物学
- 基因组学
背景情况:
- 哺乳动物的大脑发展涉及空间线索,细胞信号和遗传程序的复杂相互作用,导致超过一千种不同的细胞类型.
- 了解这一过程需要在整个时空发展范围内对细胞状态进行系统的描述.
- 单细胞RNA测序和空间转录组是揭示神经系统中的分子异质性的强大工具.
研究的目的:
- 创建一个完整的单细胞转录原子图谱,
- 在整个胚胎大脑发育过程中识别和描述细胞状态.
- 绘制关键发育基因的空间表达模式,并将其与单细胞数据集成.
主要方法:
- 从胃形成到出生,对小鼠胚胎大脑进行全面的单细胞RNA测序
- 在现场mRNA测序以确定空间基因表达模式.
- 单细胞转录组数据与空间表达数据的整合.
主要成果:
- 在小鼠胚胎大脑发育过程中识别了近800种不同的细胞状态.
- 脑功能元件的发育程序的表征,包括神经上皮,二次组织者和前代细胞.
- 通过综合数据分析精确地绘制神经元前代的空间组织.
结论:
- 这项研究提供了关于小鼠胚胎大脑发育的详细分子图谱.
- 这些发现阐明了神经祖先的发育轨迹和空间组织.
- 这种资源将促进我们对哺乳动物大脑形成和细胞多样性的理解.
相关概念视频
Hydroboration-Oxidation of Alkenes
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
Preparation of Alcohols via Addition Reactions
Overview
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
Acid-Catalyzed Dehydration of Alcohols to Alkenes
In a dehydration reaction, a hydroxyl group in an alcohol is eliminated along with the hydrogen from an adjacent carbon. Here, the products are an alkene and a molecule of water. Dehydration of alcohols is generally achieved by heating in the presence of an acid catalyst. While the dehydration of primary alcohols requires high temperatures and acid concentrations, secondary and tertiary alcohols can lose a water molecule under relatively mild conditions.
Oxidation of Alcohols
In this lesson, the oxidation of alcohols is discussed in depth. The various reagents used for oxidation of primary and secondary alcohols are detailed, and their mechanism of action is provided.
The process of oxidation in a chemical reaction is observed in any of the three forms:
The process of oxidation in a chemical reaction is observed in any of the three forms:
Preparation of Aldehydes and Ketones from Alcohols, Alkenes, and Alkynes
Aldehydes and ketones are prepared from alcohols, alkenes, and alkynes via different reaction pathways. Alcohols are the most commonly used substrates for synthesizing aldehydes and ketones. The conversion of alcohol to aldehyde, which involves the oxidation process, depends on the class of the alcohol used and the strength of the oxidizing agent. For instance, primary alcohol will form an aldehyde when treated with a weak oxidizing agent; however, it gets over-oxidized to a carboxylic acid in...
Reactions of Aldehydes and Ketones: Baeyer–Villiger Oxidation
Baeyer–Villiger oxidation converts aldehydes to carboxylic acids and ketones to esters. The reaction uses peroxy acids or peracids and is often catalyzed by acid. The reaction is named after its pioneers, Adolf von Baeyer and Victor Villiger. The reaction is achieved by a wide range of peracids such as m-chloroperoxybenzoic acid (mCPBA), perbenzoic acid (C6H5COOOH), peracetic acid (CH3COOOH), hydrogen peroxide (H2O2), and tert-butyl hydroperoxide (t-BuOOH).
The carbonyl center is activated by...
The carbonyl center is activated by...


