melanosome


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melanosome

[mə′lan·ə‚sōm]
(cell and molecular biology)
An organelle which contains melanin and in which tyrosinase activity is not demonstrable.
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8,9) Many have suggested defective transfer of melanosomes from melanocytes to keratinocytes.
Since norepinephrine (NE) could induced melanosome aggregation in fish scales [11,12,30], parallel treatment with NE was used as a positive control for pigment aggregation.
Melanocytes settle down in the epidermis and act as the guard to photoprotection and thermoregulation by packaging melanin pigment into melanosome and delivering them to neighboring keratinocytes.
29) Electron microscopy showing melanosomes rather than neurosecretory granules also helps exclude CCSLGT.
Theconstitutive skin pigmentation is regulated by a number of factors including the relative amounts of eumelanin (brown- black pigment) and pheomelanin (red-yellow pigment) synthesized within melanosomes melanocyte dendricity transport of melanosomes to dendrites and the rate of melanosome transfer to the surrounding keratinocytes (Abdel-Malek and Kadekaro2006).
At the same time, a research team from The University of Texas at Austin, the University of Akron, the China University of Geosciences and four other Chinese institutions, unexpectedly discovered that ancient maniraptoran dinosaurs, paravians, and living mammals and birds uniquely shared the evolutionary development of diverse melanosome shapes and sizes.
Melanosomes consist primarily of proteins that are synthesised in the endoplasmic reticulum (ER) and are then routed to the melanosome either directly or via the Golgi where additional modifications, such as glycosylation, are made to the protein.
Migmatization of gneisses is demonstrated by the evolution of significantly striped rocks formed by melanosome abounding in biotite and leucosome consisting of quartz, plagioclase and, to a lesser degree, of potassium spar.
Topics discussed include a history of melanosome research, classical and non-classical melanocytes in vertebrates, biosynthesis of melanins, inhibitors and enhancers of melanogenesis, structures of melanins, biogenesis of melanosomes, and the physiologicla and pathological functions of melanososmes.
4) Diagnosis can be made if the lesion is positive for antigens of melanosome, such as protein S-100 and HMB45.
Chemyunion also highlighted the efficacy of its Biolumita, a skin lightening agent with triple action whitening that reduces formation of melanosomes, as well as synthesis of melanin and melanosome transport to the keratinocytes.