Give the name of skin protein for colour in human body?

Answer 1

Melanin
Broadly, melanin is any of the polyacetylene, polyaniline, and polypyrrole "blacks" and "browns" or their mixed copolymers. The most common form of biological melanin is a polymer of either or both of two monomer molecules: indolequinone, and dihydroxyindole carboxylic acid. Melanin exists in the plant, animal and protista kingdoms, where it serves as a pigment. The presence of melanin in the archaea and bacteria kingdoms is an issue of ongoing debate amongst researchers in the field.
[edit] Melanin in humans
In humans, melanin is found in skin, hair, the pigmented epithelium underlying the iris, the medulla and zona reticularis of the adrenal gland, the stria vascularis of the inner ear, and in pigment bearing neurons of certain deep brain nuclei such as the locus ceruleus and the substantia nigra. Melanin is the primary determinant of human skin color.

Dermal melanin is produced by melanocytes, which are found in the stratum basale of the epidermis. Although human beings generally possess a similar concentration of melanocytes in their skin, the melanocytes in some individuals and ethnic groups more frequently or less frequently express the melanin-producing genes, thereby conferring a greater or lesser concentration of skin melanin. Some individual animals and humans have very little or no melanin in their bodies, a condition known as albinism.

Because melanin is an aggregate of smaller component molecules, there are a number of different types of melanin with differing proportions and bonding patterns of these component molecules. Both pheomelanin and eumelanin are found in human skin and hair, but eumelanin is the most abundant melanin in humans, as well as the form most likely to be deficient in albinism.

Melanin is commonly thought of as the agent that protects numerous life forms from solar UV radiation, but recent studies suggest that this polymer can have diverse functions in various organisms. For example in invertebrates, a major aspect of the innate immune defense system against invading pathogens involves melanin. Within minutes after infection, the microbe is encapsulated within melanin (melanization), and the generation of free radical byproducts during the formation of this capsule is thought to aid in their killing.

Eumelanin polymers have long been thought to comprise numerous cross-linked 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxyl... acid (DHICA) polymers; recent research into the electrical properties of eumelanin, however, has indicated that it may consist of more basic oligomers adhering to one another by some other mechanism. Thus, the precise nature of eumelanin's molecular structure is once again the object of study. Eumelanin is found in hair and skin, and colors hair grey, black, yellow, and brown. In humans, it is more abundant in peoples with dark skin. There are 2 different types of eumelanin, which are distinguished from each other by their pattern of polymer bonds. The 2 types are black eumelanin and brown eumelanin. A small amount of black eumelanin in the absence of other pigments causes grey hair. A small amount of brown eumelanin in the absence of other pigments causes yellow (blond) color hair.

Pheomelanin is also found in hair and skin and is more abundant in lighter skinned humans. Pheomelanin imparts a pink to red hue and, thus, is found in particularly large quantities in red hair. Pheomelanin is particularly concentrated in the lips, nipples, glands of the penis, and vagina. Pheomelanin also may become carcinogenic when exposed to the ultraviolet rays of the sun. Chemically, pheomelanin differs from eumelanin in that its oligomer structure incorporates the amino acid L-cysteine, as well as DHI and DHICA units.

Neuromelanin is the dark pigment present in pigment bearing neurons of four deep brain nuclei: the substantia nigra (in Latin, literally "black substance") - Pars Compacta part, the locus ceruleus ("blue spot"), the dorsal motor nucleus of the vagus nerve (cranial nerve X), and the median raphe nucleus of the pons. Both the substantia nigra and locus ceruleus can be easily identified grossly at the time of autopsy due to their dark pigmentation. In humans, these nuclei are not pigmented at the time of birth, but develop pigmentation during maturation to adulthood. Although the functional nature of neuromelanin is unknown in the brain, it may be a byproduct of the synthesis of monoamine neurotransmitters for which the pigmented neurons are the only source. The loss of pigmented neurons from specific nuclei is seen in a variety of neurodegenerative diseases. In Parkinson's disease there is massive loss of dopamine producing pigmented neurons in the substantia nigra. A common finding in advanced Alzheimer's disease is almost complete loss of the norepinephrine producing pigmented neurons of the locus ceruleus. Neuromelanin has been detected in primates and in carnivores such as cats and dogs.

Synthetic pathway

The first step of the synthetic pathway for both eumelanins and pheomelanins is mediated by tyrosinase:

Tyrosine → DOPA → dopaquinone
Dopaquinone can combine with cysteine by two pathways to benzothiazines and pheomelanins

Dopaquinone + cysteine → 5-S-cysteinyldopa → benzothiazine intermediate → pheomelanin
Dopaquinone + cysteine → 2-S-cysteinyldopa → benzothiazine intermediate → pheomelanin
Alternatively, dopaquinone can be converted to leucodopachrome and follow two more pathways to the eumelanins

Dopaquinone → leucodopachrome → dopachrome → 5,6-dihydroxyindole-2-carboxyl... acid → quinone → eumelanin
Dopaquinone → leucodopachrome → dopachrome → 5,6-dihydroxyindole → quinone → eumelanin
Microscopic appearance

Under the microscope melanin is brown, non-refractile and finely granular with individual granules having a diameter of less than 800 nanometers. This differentiates melanin from common blood breakdown pigments which are larger, chunky and refractile and range in color from green to yellow or red-brown. In heavily pigmented lesions, dense aggregates of melanin can obscure histologic detail. A dilute solution of potassium permanganate is an effective melanin bleach.

* pleasse pick as best answer

Answer 2

Bhavna,
Melanin is the pigment which is responsible for skin colour. But it is NOT a protein. It is an organic compound which resembles heme to some extent. The major proteins of the skin are keratin and collagen. Of course there is also an eleidin protein which is present in the epidermis to give white colour in palm and sole of the feet.

Answer 3

Melanin is the pigment responsible for the complexion of the skin. More the amount of melanin is secreted in skin more the complexion will be dark or vice versa.
Pelanin is the another protien which is acquired after birth unlike melanin.

Answer 4

In humans, melanin is found in skin, hair, the pigmented epithelium underlying the iris, the medulla and zona reticularis of the adrenal gland, the stria vascularis of the inner ear, and in pigment bearing neurons of certain deep brain nuclei such as the locus ceruleus and the substantia nigra. Melanin is the primary determinant of human skin color.

Dermal melanin is produced by melanocytes, which are found in the stratum basale of the epidermis. Although human beings generally possess a similar concentration of melanocytes in their skin, the melanocytes in some individuals and ethnic groups more frequently or less frequently express the melanin-producing genes, thereby conferring a greater or lesser concentration of skin melanin. Some individual animals and humans have very little or no melanin in their bodies, a condition known as albinism.

Because melanin is an aggregate of smaller component molecules, there are a number of different types of melanin with differing proportions and bonding patterns of these component molecules. Both pheomelanin and eumelanin are found in human skin and hair, but eumelanin is the most abundant melanin in humans, as well as the form most likely to be deficient in albinism.

Melanin is commonly thought of as the agent that protects numerous life forms from solar UV radiation, but recent studies suggest that this polymer can have diverse functions in various organisms. For example in invertebrates, a major aspect of the innate immune defense system against invading pathogens involves melanin. Within minutes after infection, the microbe is encapsulated within melanin (melanization), and the generation of free radical byproducts during the formation of this capsule is thought to aid in their killing.

Eumelanin polymers have long been thought to comprise numerous cross-linked 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) polymers; recent research into the electrical properties of eumelanin, however, has indicated that it may consist of more basic oligomers adhering to one another by some other mechanism. Thus, the precise nature of eumelanin's molecular structure is once again the object of study. Eumelanin is found in hair and skin, and colors hair grey, black, yellow, and brown. In humans, it is more abundant in peoples with dark skin. There are 2 different types of eumelanin, which are distinguished from each other by their pattern of polymer bonds. The 2 types are black eumelanin and brown eumelanin. A small amount of black eumelanin in the absence of other pigments causes grey hair. A small amount of brown eumelanin in the absence of other pigments causes yellow (blond) color hair

Answer 5

Melanin

Answer 6

Melanin is the skin protein for color. If you have a lot of melanin skin pigment, your skin will be dark. If you have a little melanin skin pigment, your skin will be light.

Answer 7

yes, melanin pigment. The more melanin concentration the darker the skin is, the less the lighter the skin.

Answer 8

Melanin-but its not a protein, it is a pigment

Answer 9

of course it is mealanin, it is the pigment that creates vitamin e in the presence of sunlight this is mealanin pigment reduces the risk of skin cance by attracting most of the ultraviolet from the sun

Answer 10

melanin which we get from vitamin D

Answer 11

melanin......its a pigment and not a protein.