Recent studies on the pigment patterns of cold-blooded vertebrates have revealed the presence of a protein melanization inhibiting factor (MIF) present in the integument of the ventral surface. This putative MIF is present in the ventral but not the dorsal surface and is presumably responsible for the pigmentary pattern seen widely among vertebrates wherein the dorsal integument is dark due to the presence of melanophores (-cytes) and the ventrum is pale due to the failure of these melanin- containing cells to differentiate. Incubation of pieces of ventral skin from Xenopus or Rana in basic salt solution (BSS) yields a conditioned medium (VCM) which when used in the culture of isolated neural tubes of Xenopus embryos, markedly inhibits on a dose-response basis, the outgrowth of neural crest cells and melanization. Preliminary experiments with S-91 murine melanoma cultures have revealed that VCM inhibits MSH-induced melanogenesis in these cells. It is not surprising that VCM from amphibian sources has an effect on a mammalian pigmentary system because pigment cells from lower and higher vertebrates alike, have much common including a neural crest origin. Because of these commonalities, it might be possible to utilize the putative MIF in human pigmentary pathologies such as vitiligo or melanoma. Accordingly, the major thrust of this research proposal is directed toward extraction and purification of the putative MIF, determination of the N-terminal amino acid sequence, synthesis of a peptide corresponding to the N-terminal acid sequence, and the preparation of polyclonal and monoclonal antibodies to MIF. These antibodies will be used for the development of radioimmunoassays to MIF, affinity purification of MIF, for fluorescent labeling of monoclonal antibodies to be used for establishing tissue localization of MIF, and for monoclonal species variations in MIF's. The effectiveness of pure MIF will be tested on other melanization systems such as mammalian melanocytes and melanoma cells in vitro.

Project Start
1988-08-01
Project End
1991-07-31
Budget Start
1989-08-01
Budget End
1990-07-31
Support Year
2
Fiscal Year
1989
Total Cost
Indirect Cost
Name
University of Arizona
Department
Type
Schools of Medicine
DUNS #
City
Tucson
State
AZ
Country
United States
Zip Code
85722
Zuasti, Adelina (2002) Melanization stimulating factor (MSF) and melanization inhibiting factor (MIF) in the integument of fish. Microsc Res Tech 58:488-95
Fukuzawa, T; Samaraweera, P; Mangano, F T et al. (1995) Evidence that MIF plays a role in the development of pigmentation patterns in the frog. Dev Biol 167:148-58
Mangano, F T; Fukuzawa, T; Johnson, W C et al. (1992) Intrinsic pigment cell stimulating activity in the skin of the leopard frog, Rana pipiens. J Exp Zool 263:112-8
Fukuzawa, T; Hamer, S J; Bagnara, J T (1992) Extracellular matrix constituents and pigment cell expression in primary cell culture. Pigment Cell Res 5:224-9
Johnson, W C; Samaraweera, P; Zuasti, A et al. (1992) Preliminary biological characterization of a melanization stimulating factor (MSF) from the dorsal skin of the channel catfish, Ictalurus punctatus. Life Sci 51:1229-36
Zuasti, A; Johnson, W C; Samaraweera, P et al. (1992) Intrinsic pigment-cell stimulating activity in the catfish integument. Pigment Cell Res 5:253-62
Bagnara, J T; Fukuzawa, T (1990) Stimulation of cultured iridophores by amphibian ventral conditioned medium. Pigment Cell Res 3:243-50
Johnson, W C; Bagnara, J T (1990) The effects of Fungizone (Amphotericin B and deoxycholic acid) on cultured B16-F10 murine melanoma cells. Pigment Cell Res 3:173-5