  It is shown that the cosmological constant links the roots both of General
Relativity and Newtonian gravity via the general function satisfying Newton's
theorem according to which the gravitating sphere acts as a point mass situated
in its center. The quantitative evidence for this link is given via the
correspondence of the current value of the cosmological constant with the value
of the cosmological term in the modified Newtonian gravity to explain the dark
matter in the galaxies. This approach reveals: (a) the nature of dark matter as
gravity's signature, (b) the common nature of dark matter and of cosmological
constant (dark energy), (c) that the dark matter as a consequence of repulsive
gravity increasing with the distance ensures the observed higher
mass-to-luminosity M/L ratio while moving from the scales of galaxies to galaxy
clusters. The galactic halos via non-force-free interaction due to the
repulsive \Lambda-term of gravity determine the features of galactic disks as
is supported by observations. The data of galaxy groups of the Hercules-Bootes
region are also shown to support the \Lambda-gravity nature of the dark matter
i.e. the value of the cosmological constant is derived not from cosmological
data. Among the consequences of such modified General Relativity is the natural
link to AdS/CFT correspondence.
