概括
身体突变,而不是重组,在B细胞分化过程中改变免疫球蛋白基因. 在髓瘤细胞中观察到的VK167基因中的这些突变发生在超变区之外,并且与V-J结合期间的DNA复制有关.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 免疫球蛋白可变区域基因在B细胞发育过程中经历重新排列和体质突变.
- VK167生殖基因在MOPC167和MOPC511骨髓瘤细胞中表达.
研究的目的:
- 为了研究B细胞分化过程中VK167基因中的遗传变化.
- 确定表达免疫球蛋白基因中核酸序列变化的机制.
主要方法:
- 生殖线和表达VK167基因的核酸测序.
- 南方斑点分析以检测限制地点的变化.
- 对生殖线和体质序列的比较分析.
主要成果:
- 在MOPC167和MOPC511细胞中表达的VK167基因与生殖系序列相比显示单基对突变.
- 这些突变改变了限制酶识别部位,证实了序列分歧.
- 南方斑点分析证实,突变的VK167序列不在生殖基因组中.
- 在框架和超变区中都发现了突变,这表明了比以前认为的更广泛的机制.
- 有证据表明,突变源于单基对替代,而不是再组合.
结论:
- 实体突变,而不是重组,是VK167基因中观察到的核酸变化的原因.
- 身体突变发生在整个变量区域中,而不仅仅发生在超变量段中.
- 提出了一个模型,建议在V-J连接过程中介绍体质突变和DNA复制之间的联系.
相关概念视频
Mutations
Overview
Antibody Structure
Overview
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibody Structure
Overview
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Immunoglobulin-like Cell Adhesion Molecules
Immunoglobulin-like cell adhesion molecules or Ig-CAMs are a versatile group of cell surface glycoproteins belonging to the immunoglobulin protein superfamily. Ig-CAMs possess the characteristic immunoglobulin protein domains and other domains such as the fibronectin type III domain. The Ig domains are glycosylated to varying degrees in different Ig-CAMs.
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
Diversity of Antigen Receptors
Antigen receptors are essential components of the immune system crucial in defending the body against foreign invaders. These receptors are present on the surface of B and T cells, enabling them to recognize antigens and mount an appropriate immune response.
Before encountering any antigen, lymphocytes express these receptors. On B cells, the antigen receptor is a membrane-bound antibody molecule called BCR; on T cells, it is a T cell receptor or TCR. B and T cell receptors are composed of two...
Before encountering any antigen, lymphocytes express these receptors. On B cells, the antigen receptor is a membrane-bound antibody molecule called BCR; on T cells, it is a T cell receptor or TCR. B and T cell receptors are composed of two...
Spontaneous and Induced Mutations
Spontaneous mutations arise infrequently during DNA replication due to errors in the process. A key factor behind these errors is tautomeric shifts in nitrogenous bases, where bases transition from keto to enol forms or amino to imino forms. This shift can alter base-pairing rules, leading to mutations. Additionally, reactive oxygen species (ROS) arising from aerobic metabolism can damage DNA, resulting in depurination (loss of a purine base) or depyrimidination (loss of a pyrimidine base).


