まとめ
研究者はヒトのβ-チューブリン多遺伝子群を分析し,1つの発現遺伝子と3つの擬似遺伝子を特定した. mRNAから派生したこれらの偽遺伝子は,数百万年前に発生した生殖線統合イベントを示しています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- ヒューマンゲノミクス (ヒトゲノミクス)
背景:
- 人間のβ-チューブリン多遺伝子族は,必要不可欠な細胞骨格タンパク質をコードする.
- 多遺伝子ファミリーの進化と構造を理解することは,遺伝子調節と機能の解読に不可欠です.
研究 の 目的:
- 3'未翻訳領域サブクローンを用いてヒトβ-チューブリン多遺伝子群を解剖する.
- このファミリー内で発現する遺伝子と擬似遺伝子を特定し,特徴づけること.
主な方法:
- 人間のβ-チューブリンcDNAクローンから3'未翻訳領域サブクローンを利用した.
- ベータチューブリン遺伝子ファミリーのメンバーの配列化と比較分析.
主要な成果:
- 4つの異なるヒトβ-チューブリン配列を特定しました: 1つの発現遺伝子と3つの内部無シドゲン.
- 発現した遺伝子は,代替ポリアデニレーションにより,2種類のmRNA種 (1.8kbと2.6kb) を生成する.
- 偽遺伝子は,処理されたmRNA統合から生じる3'ポリ (A) トラクタと側面の直接繰り返しを含んでいます.
結論:
- 3つの偽遺伝子は,1.8kbと2.6kbのmRNAのcDNAコピーから発生した.
- 擬似遺伝子の統合イベントは,4,10,1300万年前に発生したと推定されています.
- ゲルムライン発現の多遺伝子系では,RNA中間体によって生成された偽遺伝子は,おそらく配列の重要な部分を構成する.
関連する概念動画
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...
Protein Families
Protein families are groups of homologous proteins; that is, they have similarities in amino acid sequences and three-dimensional structures. Protein families usually occur because of gene duplication, where an additional copy of a gene is inserted into the genome of an organism. Mutations that change the amino acids but still allow the protein to be properly synthesized, will lead to new protein family members. If these new proteins contain similar amino acids in key locations, protein...
Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
Exon Recombination
The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes.
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Bacterial Transcription
RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
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...


