Gap junction

Japanese: ギャップ結合 - ぎゃっぷけつごう

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[Cellular communication]
In multicellular organisms, intercellular communication, which is essential for a cohesive individual, takes place at various levels. Between adjacent cells, numerous tubular protein assemblies called gap junctions are set up that penetrate the membranes of the adjacent cells. The center of the cylinder is a tunnel that connects to the cytoplasm of the adjacent cell, and molecules with a molecular weight of 1000 or less can pass through freely, so the movement of such low-molecular-weight substances can provide information.

From [Cell Adhesion]

… Ultrastructural analysis of cell-cell adhesion using electron microscopy has revealed that there are special structures or cell membrane parts involved in cell adhesion. These include desmosomes, tight junctions, zonula adherens (or intermediate junctions), and gap junctions. In epithelial cells, tight junctions, zonula adherens, and desmosomes are often arranged in sequence from the free surface of the epithelium toward the inside, forming a structure called a junctional complex. …

From [Epithelium]

…In addition to the occluded zone, there are patchy structures called desmosomes scattered between epithelial cells, which connect the cells together. There are also patchy structures called gap junctions, where the two cells are extremely close to each other, with specific protein particles between them, and a small hole in the center of this particle that connects the two cells, allowing ions to be exchanged between the cells. At the base of the epithelial cell, there is a basement membrane (basement lamina) under the cell membrane, which lines the epithelium. …

From [Myocardium]

…Compared to skeletal muscle cells, cardiac muscle cells have fewer myofibrils and more sarcoplasm. Between cardiac muscle cells there are gap junctions, which transmit excitation. Gap junctions, also known as nexuses, are devices that allow small molecules and ions to pass through and are involved in the transmission of information between cells. …

From [Smooth muscle]

…Smooth muscles are also controlled by the autonomic nervous system and cannot be moved by will (involuntary muscles). There are no special synaptic structures between nerves and smooth muscles, such as the motor endplates found in skeletal muscles, and smooth muscle cells communicate with each other through a device called a nexus (also called a gap junction), transmitting excitation. Muscle [Hisao Fujita]. …

*Some of the terminology that mentions "gap junctions" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

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【細胞間のコミュニケーション】
　多細胞生物では，まとまりのある個体としては欠かせない細胞間のコミュニケーションがいろいろなレベルで行われている。隣接細胞の間には，ギャップ結合とよばれる隣り合う細胞膜部分を貫いた多数の筒形タンパク質集合体がセットされている。筒形の中心は，隣り合う細胞の細胞質に通ずるトンネルになっており，分子量1000以下の分子は自由に通過できるので，このような低分子物質の往来が情報となりうる。…

【細胞接着】より

…　細胞間接着を電子顕微鏡を用いて微細構造レベルで解析した結果，細胞接着のための特別な構造，または細胞膜の部分のあることが知られている。接着斑(デスモソームdesmosome)，密着結合tight junction，接着帯zonula adherens(または中間結合)，狭間隙（きようかんげき）結合gap junction(ギャップ結合)などがそれである。上皮細胞ではしばしば，密着結合，接着帯，接着斑が上皮の自由表面から内側に向かって順に並び，結合複合体と呼ばれる構造を形成する。…

【上皮】より

…閉鎖帯のほかに上皮細胞間にはデスモソームdesmosomeという斑状の構造が散在しあって細胞間を接着している。またギャップ結合gap junctionとよばれる構造が斑状にちらばり，ここでは両細胞の細胞間がいちじるしく接近し，その間に特有のタンパク質粒子が介在し，この粒子の中央に両細胞をつなぐ小孔があり，細胞間のイオンの交流を行っている。上皮細胞の基底側には細胞膜の下に基底膜(基底板)があり上皮を裏打ちしている。…