<p>Enamel formation is a complex 2-step process by which proteins are
secreted to form an extracellular matrix, followed by massive protein
degradation and subsequent mineralization. Excessive systemic exposure
to fluoride can disrupt this process and lead to a condition known as
dental fluorosis. The genetic background influences the responses of
mineralized tissues to fluoride, such as dental fluorosis, observed in
A/J and 129P3/J mice. The aim of the present study was to map the
protein profile of enamel matrix from A/J and 129P3/J strains. Enamel
matrix samples were obtained from A/J and 129P3/J mice and analyzed by
2-dimensional electrophoresis and liquid chromatography coupled with
mass spectrometry. A total of 120 proteins were identified, and 7 of
them were classified as putative uncharacterized proteins and analyzed
in silico for structural and functional characterization. An interesting
finding was the possibility of the uncharacterized sequence Q8BIS2
being an enzyme involved in the degradation of matrix proteins. Thus,
the results provide a comprehensive view of the structure and function
for putative uncharacterized proteins found in the enamel matrix that
could help to elucidate the mechanisms involved in enamel
biomineralization and genetic susceptibility to dental fluorosis.</p