Melanosome

Melanosome is a cellular organelle found in animal cells. It is responsible for the synthesis, storage, and transport of melanin, the primary pigment responsible for coloration in animals. Melanosomes are found in specialized cells called melanocytes, which are primarily located in the skin, hair follicles, eyes, and inner ear.

Structure

Melanosomes are lysosome-related organelles that are bound by a lipid bilayer. They are characterized by their unique elliptical shape and high electron density. The interior of the melanosome is filled with a protein matrix that contains the enzymes necessary for melanin synthesis.

Function

The primary function of the melanosome is the synthesis of melanin. This process begins with the enzyme tyrosinase, which catalyzes the first step in melanin synthesis. The melanin is then stored within the melanosome until it is transported to the keratinocytes, the primary cell type in the skin and hair.

Role in Disease

Defects in melanosome function can lead to a variety of pigmentation disorders, including albinism and vitiligo. In addition, abnormal melanosome function has been implicated in a number of other diseases, including melanoma, a type of skin cancer.

See Also

• Melanocyte
• Melanin
• Pigmentation disorders
• Albinism
• Vitiligo
• Melanoma

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  Melanosome
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  Melanosome