Structural/functional relationships between internal and external MSH receptors: modulation of expression in Cloudman melanoma cells by UVB radiation

Journal Article · Mon Apr 01 04:00:00 EST 1991 · Journal of Cellular Physiology; (United States)

DOI:https://doi.org/10.1002/jcp.1041470102· OSTI ID:5396452

Chakraborty, A K; Orlow, S J; Bolognia, J L; Pawelek, J M ^[1]

---

1. Department of Dermatology, Yale University School of Medicine, New Haven, CT (USA)

Expression of internal receptors for MSH is an important criterion for responsiveness to MSH by Cloudman melanoma cells. Here, we show that internal and external receptors for MSH are of identical molecular weights (50-53 kDa) and share common antigenic determinants, indicating a structural relationship between the 2 populations of molecules. The internal receptors co-purified with a sub-cellular fraction highly enriched for small vesicles, many of which were coated. Ultraviolet B light (UVB) acted synergistically with MSH to increase tyrosinase activity and melanin content of cultured Cloudman melanoma cells, consistent with previous findings in the skin of mice and guinea pigs. Preceding the rise in tyrosinase activity in cultured cells, UVB elicited a decrease in internal MSH binding sites and a concomitant increase in external sites. The time frame for the UVB effects on MSH receptors and melanogenesis, 48 hours, was similar to that for a response to solar radiation in humans. Together, the results indicate a key role for MSH receptors in the induction of melanogenesis by UVB and suggest a potential mechanism of action for UVB: redistribution of MSH receptors with a resultant increase in cellular responsiveness to MSH.

• OSTI ID: 5396452
• Journal Information: Journal of Cellular Physiology; (United States), Journal Name: Journal of Cellular Physiology; (United States) Vol. 147:1; ISSN 0021-9541; ISSN JCLLA
• Country of Publication: United States
• Language: English

Related Subjects

560120* -- Radiation Effects on Biochemicals
Cells
& Tissue Culture
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL CELLS
ANIMALS
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
CELL CONSTITUENTS
CYTOPLASM
DISEASES
ELECTROMAGNETIC RADIATION
ENZYME ACTIVITY
ENZYMES
HORMONES
HYDROXY COMPOUNDS
HYDROXYLASES
KINETICS
MAMMALS
MELANIN
MELANOMAS
MEMBRANE PROTEINS
MICE
MOLECULAR WEIGHT
NEOPLASMS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDOREDUCTASES
PEPTIDE HORMONES
PIGMENTS
PITUITARY HORMONES
PROTEINS
RADIATION EFFECTS
RADIATIONS
REACTION KINETICS
RECEPTORS
RODENTS
SENSITIVITY
STRUCTURE-ACTIVITY RELATIONSHIPS
SYNERGISM
TUMOR CELLS
TYROSINASE
ULTRAVIOLET RADIATION
VERTEBRATES