T. Fukuzawa et al., EVIDENCE THAT MIF PLAYS A ROLE IN THE DEVELOPMENT OF PIGMENTATION PATTERNS IN THE FROG, Developmental biology, 167(1), 1995, pp. 148-158
A ventrally localized melanization-inhibiting factor (MIF) may play an
important role in the expression of dorsal-ventral pigment patterns o
f amphibians. In efforts to purify this putative MIF, ventral skin con
ditioned medium (VCM) from Rana forreri was partially fractionated and
used to immunize mice. A monoclonal antibody that has the ability to
block the activity of MIP was isolated, and an immunoaffinity matrix w
as prepared by cross-linking the antibody to protein G-Sepharose. The
fraction of VCM that bound to the affinity matrix decreased the number
of melanized cells in the Xenopus laevis neural tube explant assay, b
ut did not reduce significantly the number of cells that emigrated. Th
e monoclonal antibody was used for immunohistochemical studies on R. p
ipiens skin. Strong staining with the antibody was observed beneath th
e basement membrane, in mucous glands, and in the subcutaneous tissue
of the ventral skin. A weak staining was also observed in the ground s
ubstances of both ventral and dorsal skin. These results confirm that
a monoclonal antibody has been secured against at least one of the MIF
constituents and that it is useful as a probe in detecting the distri
bution of MIF in tissues. The results of its use in this study support
the hypothesis that MIF plays a role in the expression, development,
and maintenance of the dorsal-ventral pigmentation patterns of frogs.
(C) 1995 Academic Press, Inc.