T-box遺伝子 tbx5は,胸肢の芽形成に不可欠である
Dae-gwon Ahn1, Matthew J Kourakis, Laurel A Rohde
1Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois 60637, USA. dahn@midway.uchicago.edu
Nature
|June 18, 2002
まとめ
Tbx5は,手足の芽の形成に先立つゼブラフィッシュの胸の発達に不可欠です. Tbx5のノックダウンは,メソダーマ細胞の移動を妨害し,の発達を阻害する.
科学分野:
- 発達生物学 発達生物学について
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
背景:
- Tボックス遺伝子 (Tbx4,Tbx5) は,脊椎動物の四肢のアイデンティティに不可欠です.
- Tbx5は前肢のアイデンティティを指定し,Tbx4は後肢のアイデンティティを指定します.
研究 の 目的:
- 斑馬魚の発達におけるTbx5の初期の機能を調査する.
- 胸の形成におけるTbx5の役割を決定する.
主な方法:
- アンチセンスオリゴヌクレオチドを用いて,ゼブラフィッシュのtbx5遺伝子発現を低下させた.
- 羽根の芽の形成と胸の羽根の発達に対する観察された効果.
主要な成果:
- Tbx5のノックダウンは,胸の芽の開始を妨げ,胸の完全な喪失を引き起こしました.
- Tbx5の機能には,横板メソダーマ細胞の指向された移動が含まれています.
- 欠陥は,スパデータイル (ゼブラ魚) とブラキューリ (マウス) の変異体と似ている.
結論:
- Tbx5は,手足の芽が形成される前に,ゼブラフィッシュの胸の発達に不可欠な早期の役割を果たしています.
- Tbx5は,Tボックス遺伝子の間で保存された機能であるメソダーマ細胞の移動を調節します.
- Tボックス遺伝子は,胚の発達初期に細胞の移動と結合を一般的に制御する可能性があります.
関連する概念動画
01:33Pleiotropy
Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...
02:16Transcription 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...
01:30General 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...
01:16TGF - β Signaling Pathway
The TGF-β signaling pathway regulates cell growth, differentiation, adhesion, motility, and development. TGF-β ligands that induce TGF-β signaling are synthesized in their latent form. Several proteases or cell surface receptors such as integrins act upon the latent form, releasing the active ligand. There are three types of mammalian TGF-βs: (TGF-β1, TGF-β2, and TGF-β3) that bind as homodimers or heterodimers to TGF-β receptors. The TGF-β receptors are of three kinds RI, RII, and RIII. The RI...
01:31Bone Remodeling and Repair
Osteoclasts are cells responsible for bone resorption and remodeling. They originate from hematopoietic progenitor cells present in the bone marrow. Numerous progenitor cells fuse to form multinucleated cells, each with 10-20 nuclei. A single osteoclast has a diameter of 150 to 200 µM. These cells have ruffled borders that break down the underlying bone tissue and release minerals such as calcium into the blood in bone resorption. Osteoclasts cling to bones with their ruffled edges during bone...
01:24Bone Formation by Endochondral Ossification
Bone formation, or ossification, begins around the sixth to seventh week of embryonic development. Most bones develop from a cartilaginous template through the process of endochondral ossification. Cartilage formation begins when clusters of mesenchymal cells differentiate into chondrocytes. These chondrocytes proliferate rapidly and secrete an extracellular matrix that becomes encased in a membrane called the perichondrium. The resulting cartilage model provides a template that resembles the...