  We argue that extra dimensions with a properly chosen compactification scheme
could be a natural source for emergent gauge symmetries. Actually, some
proposed vector field potential terms or polynomial vector field constraints
introduced in five-dimensional Abelian and non-Abelian gauge theory is shown to
smoothly lead to spontaneous violation of an underlying 5D spacetime symmetry
and generate pseudo-Goldstone vector modes as conventional 4D gauge boson
candidates. As a special signature, there appear, apart from conventional gauge
couplings, some properly suppressed direct multi-photon (multi-boson, in
general) interactions in emergent QED and Yang-Mills theories whose observation
could shed light on their high-dimensional nature. Moreover, in emergent
Yang-Mills theories an internal symmetry G also occurs spontaneously broken to
its diagonal subgroups once 5D Lorentz violation happens. This breaking origins
from the extra vector field components playing a role of some adjoint scalar
field multiplet in the 4D spacetime. So, one naturally has the Higgs effect
without a specially introduced scalar field multiplet. Remarkably, when being
applied to Grand Unified Theories this results in a fact that the emergent GUTs
generically appear broken down to the Standard Model just at the 5D Lorentz
violation scale M.
  PACS numbers: 11.15.-q, 11.30.Cp, 11.30.Pb, 11.10.Kk
