In:
Pigment Cell & Melanoma Research, Wiley, Vol. 27, No. 5 ( 2014-09), p. 831-834
Abstract:
Melanin within melanosomes exists as eumelanin or pheomelanin. Distributions of these melanins have been studied extensively within tissues, but less often within individual melanosomes. Here, we apply X‐ray fluorescence analysis with synchrotron radiation to survey the nanoscale distribution of metals within purified melanosomes of mice. The study allows a discovery‐based characterization of melanosomal metals, and, because Cu is specifically associated with eumelanin, a hypothesis‐based test of the ‘casing model’ predicting that melanosomes contain a pheomelanin core surrounded by a eumelanin shell. Analysis of Cu, Ca, and Zn shows variable concentrations and distributions, with Ca/Zn highly correlated, and at least three discrete patterns for the distribution of Cu vs. Ca/Zn in different melanosomes – including one with a Cu‐rich shell surrounding a Ca/Zn‐rich core. Thus, the results support predictions of the casing model, but also suggest that in at least some tissues and genetic contexts, other arrangements of melanin may co‐exist.
Type of Medium:
Online Resource
ISSN:
1755-1471
,
1755-148X
DOI:
10.1111/pcmr.2014.27.issue-5
Language:
English
Publisher:
Wiley
Publication Date:
2014
detail.hit.zdb_id:
2425880-5
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