组织素H3K4脱甲基酶SMCX将REST目标基因与X相关的智力障碍联系起来
Mamta Tahiliani1, Pinchao Mei, Rui Fang
1Division of Endocrinology, Diabetes, and Hypertension, Department of Medicine and BCMP, Brigham and Women's Hospital and Harvard Medical School, 221 Longwood Avenue Boston, Massachusetts 02115, USA.
Nature
|May 1, 2007
概括
通过去除H3K4三甲基化,JARID1C/SMCX作为转录抑制剂. 它的损失损害了神经元基因调节,可能导致X相关的精神障碍.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 分子生物学分子生物学
- 神经科学是一个神经科学.
背景情况:
- 基因转录是由染色质结构和基因素尾部修改调节的.
- 基因组甲基化是由基因组甲基转移酶和脱甲基酶动态控制的.
研究的目的:
- 为了研究JARID1C/SMCX的功能,一个与X相关的精神迟缓和相关的蛋白质.
- 确定JARID1C/SMCX在基因转录和染色质调节中的作用.
主要方法:
- 从HeLa细胞中生物化学分离SMCX复合体.
- 染色体免疫沉 (ChIP) 评估基因促进者的蛋白质占用率.
- 通过RNA干扰 (RNAi) 来消耗SMCX并分析基因表达变化.
主要成果:
- JARID1C/SMCX表现出H3K4三甲基酶活性,并作为转录抑制剂起作用.
- SMCX与基因素脱乙酶 (HDAC1,HDAC2),G9a和REST) 形成一个复合体.
- SMCX和REST共同定位在REST目标基因的神经元限制性沉默元件上.
- SMCX 枯竭导致 REST 基因的减压,并在特定的神经元基因促进体 (SCN2A,SYN1) 上增加 H3K4 三甲基化.
结论:
- JARID1C/SMCX在染色质动态和REST介导的转录抑制中发挥着关键作用.
- 失去了SMCX活动会破坏神经元基因调节,导致X相关的精神障碍.
- SMCX作为H3K4三甲基酶起作用,参与神经元基因的表观遗传调节.
相关概念视频
Inheritance of Chromatin Structures
Epigenetics is the study of inherited changes in a cell's phenotype without changing the DNA sequences. It provides a form of memory for the differential gene expression pattern to maintain cell lineage, position-effect variegation, dosage compensation, and maintenance of chromatin structures such as telomeres and centromeres. For example, the structure and location of the centromere on chromosomes are epigenetically inherited. Its functionality is not dictated or ensured by the underlying DNA...
Epigenetic Regulation
Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
Epigenetic Regulation
Epigenetic changes alter the physical structure of the DNA without changing the genetic sequence and often regulate whether genes are turned on or off. This regulation ensures that each cell produces only proteins necessary for its function. For example, proteins that promote bone growth are not produced in muscle cells. Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
X-chromosome...
X-chromosome...
Heterochromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions that take up more dye are called heterochromatin. Heterochromatin is further classified into two forms – constitutive heterochromatin and facultative heterochromatin.
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Euchromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions take up more dye, appearing darker, while the less-compact areas take up less dye and appear lighter. Based on the compaction level, chromatins are classified into two primary forms – euchromatin and heterochromatin.
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
Spreading of Chromatin Modifications
The histone proteins in the nucleosomes are post-translationally modified (PTM) to increase or decrease access to DNA. The commonly observed PTMs are methylation, acetylation, phosphorylation, and ubiquitination of lysine amino acids in the histone H3 tail region. These histone modifications have specific meaning for the cell. Hence, they are called "histone code". The protein complex involved in histone modification is termed as "reader-writer" complex.
Writers
The writer is an enzyme that can...
Writers
The writer is an enzyme that can...


