概括
研究人员确定了12个Xenopus laevis全球蛋白基因,分为两个群. 这些基因,包括幼虫和成人的α和β类型,表现出独特的对称布局,并且具有比较高的脊椎动物更大的内核.
科学领域:
- 基因组学就是基因组学.
- 分子生物学分子生物学
- 发育生物学 发展生物学
背景情况:
- 全球蛋白基因家族对氧气运输必需的蛋白质进行编码.
- 了解全球蛋白基因组织,可以深入了解基因调节和进化.
研究的目的:
- 从Xenopus laevis中分离和描述全球蛋白基因.
- 确定Xenopus laevis全球蛋白基因家族的排列和结构.
主要方法:
- 使用两个基因组库,从Xenopus laevis中分离基因组克隆.
- 基因序列测序和基因顺序和转录极性分析.
- 电子显微镜用于基因结构分析.
主要成果:
- 鉴定了12个Xenopus laevis全球蛋白基因,包括幼虫和成人的α和β类型.
- 基因被组织成两个集群,对称地排列.
- 克塞诺普斯全球基因有三个外体和两个内体,与较高的脊椎动物相比,内体显著更大.
结论:
- 谢诺普斯 (Xenopus laevis) 全球蛋白基因家族是复杂的,具有独特的集群和对称组织.
- 在Xenopus球蛋白基因中的大型内子可能在基因调节或进化中发挥作用.
相关概念视频
Gene Families
Gene families consist of groups of genes proposed to have originated from a common ancestor. Typically these arise through events in which a gene or genes are mistakenly duplicated during cell division. Unlike their parent genes (which are subject to selection pressure to maintain function), these gene copies do not need to preserve their sequences and may evolve at a relatively faster rate.
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Position-effect Variegation
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
Lampbrush Chromosomes
In 1882, Flemming observed lampbrush chromosomes (LBC) in salamander eggs. Later in 1892, Rückert observed LBCs in shark egg cells and coined the term "lampbrush chromosomes" because they looked like brushes used to clean kerosene lamps.
LBCs are made up of two pairs of conjugating homologous chromatids. Each chromatid consists of alternatively positioned regions of condensed-inactive chromatin and loosely placed-active side loops, which can be contracted and extended. The loops resemble the...
LBCs are made up of two pairs of conjugating homologous chromatids. Each chromatid consists of alternatively positioned regions of condensed-inactive chromatin and loosely placed-active side loops, which can be contracted and extended. The loops resemble the...
Chromatin Position Affects Gene Expression
Chromatin is the massive complex of DNA and proteins packaged inside the nucleus. The complexity of chromatin folding and how it is packaged inside the nucleus greatly influences access to genetic information. Generally, the nucleus' periphery is considered transcriptionally repressive, while the cell's interior is considered a transcriptionally active area.
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the timing and level of...
Topologically Associated Domains (TADs)
The 3-dimensional positioning of chromatin in the nucleus influences the timing and level of...
General Transcription Factors
Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...
Lampbrush Chromosomes
In 1882, Flemming observed lampbrush chromosomes (LBC) in salamander eggs. Later in 1892, Rückert observed LBCs in shark egg cells and coined the term "lampbrush chromosomes" because they looked like brushes used to clean kerosene lamps.
LBCs are made up of two pairs of conjugating homologous chromatids. Each chromatid consists of alternatively positioned regions of condensed-inactive chromatin and loosely placed-active side loops, which can be contracted and extended. The loops resemble the...
LBCs are made up of two pairs of conjugating homologous chromatids. Each chromatid consists of alternatively positioned regions of condensed-inactive chromatin and loosely placed-active side loops, which can be contracted and extended. The loops resemble the...


