Name: collagen fibers give tissues strength
Uploaded: 2023-04-30T11:52:54.000Z
Duration: 1 min 13 s
Channel: JoVE

Collagens are one of the most commonly found proteins in mammals. They are known for their high tensile strength and provide excellent resistance to pulling forces. Collagens are basically fibrous proteins exclusively found in the extracellular matrix.
They are primarily produced by fibroblasts and in smaller quantities by smooth muscle cells and epithelial cells.
Collagen molecules are trimers consisting of three polypeptide chains, called alpha chains. These chains are rich in glycine, proline and hydroxyproline, necessary for structural stability and triple-stranded helix formation.&#160;
In the case of fibrillar collagen, these trimers or protocollagens first assemble into collagen fibrils. Then, these fibrils assemble into collagen fibers, forming tendons that attach muscle to bone, rendering a stable framework for tissues.
Conversely, non-fibrillar collagens, such as type IV collagen, do not form fibrils. They are an important component of basal lamina, which separates cells from other cells and from connective tissue.

collagens are the major structural proteins of ecm

Collagens are the Major Structural Proteins of ECM

Three main types of fibers are secreted by fibroblasts: collagen fibers, elastic fibers, and reticular fibers. Collagen fiber is made from fibrous protein subunits linked together to form a long, straight fiber. Collagen fibers, while flexible, have great tensile strength, resist stretching, and give ligaments and tendons their characteristic resilience and strength. These fibers hold connective tissues together, even during the body&#39;s movement.
Connective tissue proper includes loose connective tissue and dense connective tissue. Dense connective tissue contains more collagen fibers than does loose connective tissue. As a consequence, it displays greater resistance to stretching. Dense regular elastic tissue contains elastin fibers and collagen fibers, allowing the ligament to return to its original length after stretching. The skin&#39;s dermis is an example of dense irregular connective tissue rich in collagen fibers. Hyaline cartilage, the most common type of cartilage in the body, consists of short and dispersed collagen fibers and contains large amounts of proteoglycans. Fibrocartilage is tough because it has thick bundles of collagen fibers dispersed through its matrix. Menisci in the knee joint and the intervertebral discs are examples of fibrocartilage. Elastic cartilage contains elastic fibers as well as collagen and proteoglycans.
This text is adapted from<a href="https://openstax.org/books/anatomy-and-physiology-2e/pages/4-3-connective-tissue-supports-and-protects"> Openstax, Anatomy and physiology 2e, Section 4.3: Connective tissue supports and protects.</a>

Three main types of fibers are secreted by fibroblasts: collagen fibers, elastic fibers, and reticular fibers. Collagen fiber is made from fibrous protein ...

collagens-are-the-major-structural-proteins-of-ecm

Education

JoVE Core

Cell Biology

Unit 1

Extracellular Matrix in Animals

KEY TERMS AND CONCEPTS

collagen fibers give tissues strength

Collagen fibers give connective tissues strength and help them resist stretching. They are one of three main fiber types secreted by fibroblasts, along with elastic fibers and reticular fibers. Collagen fibers are made from fibrous protein subunits linked into long, straight fibers.

These fibers are flexible, but they also have great tensile strength. Tensile strength is the ability to resist pulling forces. Collagen fibers help ligaments and tendons stay resilient and strong. They also hold connective tissues together during body movement.

Connective tissue proper includes loose connective tissue and dense connective tissue. Dense connective tissue has more collagen fibers than loose connective tissue. Because of this, it resists stretching more strongly. Dense regular elastic tissue contains both elastin fibers and collagen fibers, so a ligament can return to its original length after stretching. The dermis of the skin is an example of dense irregular connective tissue rich in collagen fibers.

Collagen fibers also appear in cartilage. Hyaline cartilage, the most common cartilage in the body, has short and dispersed collagen fibers and large amounts of proteoglycans. Fibrocartilage is tough because it contains thick bundles of collagen fibers spread through its matrix. Menisci in the knee joint and the intervertebral discs are examples of fibrocartilage. Elastic cartilage contains elastic fibers, as well as collagen and proteoglycans.

Collagen Fibers Give Tissues Strength

the extracellular matrix

How the Extracellular Matrix Shapes Tissues

The extracellular matrix, or ECM, helps animal tissues stay organized and keeps cells in the right place. It is made of structural molecules that support tissue shape and give certain tissues their special properties. The ECM usually contains a gel-like ground substance, fibrous parts, and many molecules with different jobs. One major group is glycosaminoglycans, or GAGs, which are polysaccharides. GAGs fill much of the space outside cells and can take up a large volume compared with their...

glycosaminoglycans

GAGs in Tissue Support and Lubrication

Glycosaminoglycans, or GAGs, are long, linear polymers that help build and protect animal tissues. They are also called mucopolysaccharides. Their repeating units are made of an amino sugar, such as N-acetylglucosamine or N-acetylgalactosamine, plus a uronic acid, usually glucuronic acid or iduronic acid. GAGs are found in the extracellular matrix of vertebrates, invertebrates, and bacteria. Their polar nature lets them attract water. This makes them useful as lubricants and as shock absorbers...

Collagen fibers give connective tissues strength and help them resist stretching. They are one of three main fiber types secreted by fibroblasts, along with elastic fibers and reticular fibers. Collagen fibers are made from fibrous protein subunits linked into long, straight fibers. These fibers are flexible, but they also have great tensile strength. Tensile strength is the ability to resist pulling forces. Collagen fibers help ligaments and tendons stay resilient and strong. They also hold...

fibril-associated collagen

FACIT Collagens in the Extracellular Matrix

FACIT collagens are fibril-associated collagens found in the extracellular matrix. FACIT stands for fibril-associated collagens with interrupted triple helices. These collagens help connect collagen fibrils to each other and to other extracellular matrix proteins. Type II collagen fibrils in cartilage provide a clear example. They have covalently bound type IX fibril-associated collagens at regular intervals. Other FACIT collagens include types XII, XIV, XVI, XIX, XX, XXI, and XXII. These...

elastin is responsible for tissue elasticity

elastin-is-responsible-for-tissue-elasticity

Elastic Tissues in Skin, Vessels, and Ears

Elastic tissues contain elastin, a protein mixed with smaller amounts of other proteins and glycoproteins. Elastin helps tissue return to its original shape after it is stretched or compressed. This property is important in body parts that must bend, stretch, and recoil. Elastic fibers are found in elastic tissues in the skin and in the elastic ligaments of the vertebral column. Ligaments and tendons are both made of dense regular connective tissue, but ligaments do not always have all of...

fibronectins connect cells with ecm

Fibronectin and Cell Attachment in ECM

Fibronectin is an adhesive glycoprotein in the extracellular matrix of embryogenic and adult tissue. It helps regulate cell motility and attachment. In many tissues, fibronectin gives cells a place to bind and move along. A fibronectin molecule is made of two identical polypeptide chains. These chains are joined at the C-terminal by a pair of disulfide bonds. Fibronectin also binds proteoglycans and collagen. It then links to integrin proteins, which interact with transmembrane proteins in the...

matrix proteoglycans and glycoproteins

Extracellular Matrix Support Proteins

Proteoglycans and matrix glycoproteins help build the extracellular matrix. The extracellular matrix is the material outside cells that gives tissues support and structure. Proteoglycans are heavily glycosylated proteins, and they are commonly found woven through collagen fibers. Hyaline cartilage shows how proteoglycans work. This is the most common type of cartilage in the body. It contains short, scattered collagen fibers with large amounts of proteoglycans. The proteoglycans carry long...

role of matrix metalloproteases in degradation of ecm

role-of-matrix-metalloproteases-in-degradation-of-ecm

How MMPs Remodel the Extracellular Matrix

Matrix metalloproteases (MMPs) are enzymes that break down proteins and glycoproteins in the extracellular matrix, or ECM. The ECM is the dense network around cells. By cutting ECM molecules, MMPs help cells move and grow through tissue. MMPs are important during embryonic development and morphogenesis, the process that shapes body form. A classic example comes from a tadpole’s tail during metamorphosis. The first MMP activity discovered was a collagenase, an enzyme that cuts collagen. This...

basal lamina are the specialized form of ecm

basal-lamina-are-the-specialized-form-of-ecm

Basal Lamina Structure and Cell Attachment

The basal lamina is a thin extracellular layer that sits beneath cells and separates them from other tissues. It acts as a support layer for epithelium and helps anchor it to the tissue below. Its structure includes three layers: lamina lucida, lamina densa, and lamina reticularis. The basal lamina is made of glycoproteins and collagen. Key proteins in this framework include laminins, perlecan, entactin, and type IV collagen. Cell membrane proteins such as integrins and dystroglycan bind to...

laminins are the adhesive proteins of basal lamina

laminins-are-the-adhesive-proteins-of-basal-lamina

Laminin Structure and Basal Lamina Support

Laminins are large extracellular matrix proteins that help build the basal lamina. Each laminin molecule has three chains: alpha, beta, and gamma. These chains are encoded by five alpha genes, four beta genes, and three gamma genes. In humans, the alpha chains are LAMA1, LAMA2, LAMA3, LAMA4, and LAMA5. The beta chains are LAMB1, LAMB2, LAMB3, and LAMB4. The gamma chains are LAMC1, LAMC2, and LAMC3. Laminin types are named based on which three chains they contain. Laminins join with one...

type iv collagen of basal lamina

Type IV Collagen in Basement Membranes

Type IV collagen is a network-forming collagen found in basement membranes. It acts as a barrier between epithelial and endothelial cells. It also helps form the backbone of the basement membrane with laminin, entactin, proteoglycans, and fibronectin. Beyond support, type IV collagen also helps with signaling functions linked to normal body processes and disease. A type IV collagen molecule contains six alpha chains. These chains can form at least three heterotrimeric triple-helical...

key terms and concepts

Learn how collagen fibers support connective tissues, resist stretching, and help form ligaments, tendons, skin dermis, and cartilage in the body.

Collagen Fibers Give Tissues Strength | JoVE K12

cell biology

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Collagen Fibers Give Tissues Strength

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