在Cryptosporidium parvum中解读转录:多基因基因表达和染色体可访问性
Rui Xiao1,2, Rodrigo P Baptista1,3,4, Fiifi Agyabeng-Dadzie5
1Institute of Bioinformatics, University of Georgia, Athens, GA, 30602, USA.
bioRxiv : the preprint server for biology
|January 27, 2025
概括
之前认为罕见的多基斯特龙mRNA表达,现在已被证实在复合体寄生虫Cryptosporidium parvum中. 这一发现揭示了这一医学上重要的生物体中新的一层基因调节.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 寄生虫学的寄生虫学
背景情况:
- 多基因基因被转录为单个单元的多基因基因 (polycistronic mRNA) 在真核生物中被认为是罕见的.
- 最近的发现已经确定了多基斯特龙转录在不同的生物体,如藻类,真菌,和kinetoplastids.
- 它在一个重要的寄生虫群 - - 复合体中的存在,在很大程度上是未被探索的.
研究的目的:
- 调查并提供综合证据,对多基斯特龙mRNA表达在apicomplexan寄生虫Cryptosporidium parvum.提供全面的证据.
- 描述这些多基斯特朗转录的性质和调节.
- 了解对复合体中的基因调节的影响.
主要方法:
- 在多种寄生虫菌株和技术中利用长读RNA测序 (RNA-seq).
- 用人逆转录聚合酶连锁反应 (RT-PCR) 用于转录验证.
- 在杂虫中进行ATAC测序 (使用测序测定转化酶可访问的染色质) 以评估染色质可访问性.
主要成果:
- 证明了Cryptosporidium parvum中定义的多基斯特朗基特的存在,通常含有2-4个蛋白质编码基因.
- 观察了一些多基斯特龙的差异表达,包括在发育过程中生成内部单基斯特龙转录.
- 发现多基斯特龙转录通常在他们的5-prime末端表现出一个单一的开放色素峰值,其中有一个E2F结合点.
结论:
- 这项研究提供了第一份关于虫复合体寄生虫中多基斯特龙转录的报告.
- 在Cryptosporidium parvum中,多基斯特龙mRNA表达代表了基因调节的重要层.
- 这些发现扩大了对医学上重要的杂生物体基因表达策略的理解.
相关概念视频
02:32Position-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.
02:25Spreading 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...
02:35Chromatin 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...
02:41Chromatin Structure Regulates pre-mRNA Processing
In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
The chromatin structure, especially...
01:58Prokaryotic Transcriptional Activators and Repressors
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Transcription of prokaryotic...
02:36Chromatin Immunoprecipitation- ChIP
Chromatin immunoprecipitation, or ChIP, is an antibody-based technique used to identify sites on DNA that bind to transcription factors of interest or histone proteins. It also helps determine the type of histone modifications such as acetylation, phosphorylation, or methylation.
Types of ChIP
ChIP can be divided into two types - X-ChIP and N-ChIP. X-ChIP involves in vivo cross-linking of histones and regulatory proteins to DNA, fragmenting the DNA by sonication, and isolating the protein-DNA...
Types of ChIP
ChIP can be divided into two types - X-ChIP and N-ChIP. X-ChIP involves in vivo cross-linking of histones and regulatory proteins to DNA, fragmenting the DNA by sonication, and isolating the protein-DNA...