What junctions are in intercalated discs?
Intercalated discs contain three different types of cell-cell junctions:
- Fascia adherens junctions (anchoring junctions) where actin filaments attach thin filaments in the muscle sarcomeres to the cell membrane.
- Expanded desmosomes.
- Gap junctions.
What are the two intercellular junctions in intercalated discs?
Intercalated discs are part of the sarcolemma and contain two structures important in cardiac muscle contraction: gap junctions and desmosomes. A gap junction forms channels between adjacent cardiac muscle fibers that allow the depolarizing current produced by cations to flow from one cardiac muscle cell to the next.
What are intercalated discs and what junctions exist there?
Intercalated disks represent the undulating double membranes where two cells are tightly bound together by desmosomes and connected by gap junctions, allowing electrical impulse conduction from cell to cell.
What intercellular junctions are present in cardiac tissue?
Cardiac muscle cells are equipped with three distinct types of intercellular junction–gap junctions, “spot” desmosomes, and “sheet” desmosomes (or fasciae adherentes)–located in a specialized portion of the plasma membrane, the intercalated disk.
Where are adhesion junctions found?
Adherens junctions (or zonula adherens, intermediate junction, or “belt desmosome”) are protein complexes that occur at cell–cell junctions, cell–matrix junctions in epithelial and endothelial tissues, usually more basal than tight junctions.
What is interconnected disc?
Intercalated discs are cross-bands that separate the opposite ends of myocytes. They help to hold the adjacent cells together and transmit the force of contraction from cell to cell. These discs allow diffusion of ions across the cells due to which muscle impulses travel rapidly from cell to cell.
Are intercalated discs gap junctions?
muscle cells, unique junctions called intercalated discs (gap junctions) link the cells together and define their borders. Intercalated discs are the major portal for cardiac cell-to-cell communication, which is required for coordinated muscle contraction and maintenance of circulation.
What are the 3 intercellular junctions?
Three different types of intercellular junctions can be distinguished according to their function:
- Tight or occluding junctions.
- Adherent or anchoring junctions, including desmosomes and hemidesmosomes.
- Gap junctions.
How many types of intercellular junctions are there?
Two types of intercellular junctions are established at the level of the lateral surface of epithelial cells: tight junctions (TJs) and adherens junctions (AJs).
What are intercellular junctions?
Intercellular junctions are specialized regions of contact between the plasma membranes of adjacent cells. They are essential to any multicellular organism, providing the structural means by which groups of cells can adhere and interact.
