Neuromelanin is similar to eumelanin
, but its function in the brain is only partially understood.
In dovekies, as in auks, the black colour is completely caused by eumelanin
(van Grouw, 2006), and thus the observed individual represents the "brown" aberration, in which the appearance of the eumelanin
in feathers is changed.
A sex-linked recessive mutation known as "brown" (for example Carefoot 1996) results from incomplete oxidation of eumelanin
and yields brown plumage instead of black, which can become paler from effects of sunlight (van Grouw 2006).
Chinchilla mutations permit transmission of eumelanin
, which generally comprises the spots, blotches, and stripes typically occurring on most patterned felids.
An analogue of a-MSH, SCENESSE (R) is a linear peptide which activates the skin to release eumelanin
, the dark pigment which is known to have photoprotective properties (providing skin protection against light and UV radiation).
Melanins are classified in: Allomelanin (Allo) present in plants and fungi, Neuromelanin (Neu) present in nervous cell, Pheomelanin (Pheo) and Eumelanin
(Eu) that can be found in the skin, hair and iris.
There are two chemical forms of pigment in human hairs: eumelanin
Hair colour at birth depends upon how much of the two types of melanin - Eumelanin
and Pheomelanin - they produce.
Towards structure-property-function relationships for eumelanin
The murine Agouti gene encodes a paracrine signaling molecule that promotes follicular melanocytes to produce yellow phaeomelanin pigment instead of black eumelanin
There are two different types of melanin, eumelanin
with black pigments and phaeomelanin with yellow pigments.
Its first role is to disrupt some of the chemical bonds found in eumelanin
and phaeomelanin, the natural pigments responsible for black to brown and red to yellowish hair respectively.