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Comments: Slc7a gene encoding plasma membrane cystine/glutamate exchanger was identified as
a major genetic regulator of phaeomelanin production with minimal effects on eumelanin. Cells
from sut mice (mutant in Slc7a11gene) were reported to have moderate deficiences of electron
microscopy observable platelet dense granules, but in this study no changes in EM appearance of
melanosomes were found. In sut melanocytes grown in vitro in the absence of ß-mercaptoethanol
increased DOPA staining of tubular/vesicle structure (possibly the trans Golgi network) was noted
unlike cells grown in the presence of ß-mercaptoethanol.
- Fowler DM, Koulov AV, Alory-Jost C, Marks MS, Balch BE, Kelly JW.
Functional amyloid formation within mammalian tissue. PLOS Biology 4(1): e6, 2006
Comments: Amyloid structure of melanosome fibrils was deduced from experiments based on the
binding of dyes that fluoresce upon interaction with a cross-β sheet structures and on the ability to
reconstitute Pmel17 amyloid formation in vitro as demonstrated by various biophysical
techniques (X-ray fiber diffraction, CD and FT-IR spectra).
- Fukunaga M.
Perivascular epitheloid cell tumor of the uterus: Report of four cases. Int J Gynecol Pathol
24(4): 341-346, 2005.
- Hachiya A, Sriwiriyanont P, Kaiho E, Kitahara T, Takema Y, Tsuboi R.
An in vivo mouse model of human skin substitute containing spontaneously sorted
melanocytes demonstrates physiological changes after UVB irradiation. J Invest Dermatol
125(2): 364-372, 2005.
Comments: Melanosome transfer to keratinocytes was correctly reorganized and melanin
(melanosomes) evenly dispersed in the basal and suprabasal layers. The colour of human skin
substitutes was found darker when cells of African descent were used in comparison to those of
Caucasian origin.
- Immerstrand C, Nilsson MH, Lindroth M, Sundquist T, Magnusson KE, Peterson KH.
Height changes associated with pigment aggregation in Xenopus laevis melano-phores.
Bioscience Rep 24(3): 203-214, 2004.
Comments: Melanosome aggregation in X. laevis melanophores resulted in a significant height
increase across the cell centre, which was substantially larger when aggregation was induced by
latrunculin than with melatonin. The elevation of the plasma membrane did not correlate with the
influx of water through aquaporins or formation of new microtubules; rather the accumulation of
pigment granules seemed to drive the change in cell height.
- Iyengar P, DeAngelis DD, Greenberg M, Taylor G.
Perivascular epitheloid cell tumor of the orbit: A case report and review of the literature.
Pediatric Develop Pathol 5, 98-104, 2005.
Comments: A report of orbit PEComa showing on EM examination the presence of abnormal
premelanosomes. Tumor cells were positive for HMB-45, tyrosinase, calponin and smooth muscle
actin. Differential diagnosis between PEComa and melanoma, which can be pretty difficult, was
discussed in detail.
- Levi V, Serpinskaya AS, Gratton E, Gelfand V.
Organelle transport along microtubules in Xenopus melanophores: Evidence for cooperation
between multiple motors. Biophys J Oct 7, 2005 /Epub ahead of print/
Comments: The regulation of melanosome transport along microtubules was explored in vivo. The
melanosome velocity depended linearly on the number of active motors. According to the authors
1 to 3 dynein molecules transport each melanosome in the minus end direction. The transport in the
plus end direction was mainly driven by 1 to 2 copies of kinesin-2. The number of dyneins
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