  We propose the approach to deriving lower-dimensional limit of modern
high-energy theory which does not make explicit use of the Kaluza-Klein scheme
and predefined compactification manifolds. The approach is based on the
selection principle in which a crucial role is played by p-brane solutions and
their preservation, in a certain sense, under dimensional reduction. Then we
engage a previously developed method of reconstruction of a theory from a given
solution which eventually leads to some model acting in the space of field
couplings. Thus, our approach focuses on those general features of effective 4D
theories which are independent of how the decomposition of spacetime dimensions
into ``observable'' and ``unobservable'' ones could be done. As an example, we
exactly derive the simplified abelian sector of the effective low-energy
M-theory together with its fundamental 0-brane solution describing the family
of charged black holes with scalar hair in asymptotically flat, de Sitter or
anti-de Sitter spacetime.
