[en] Recent data give some indications in favor of the Large Mixing Angle (LMA) MSW-solution of the solar neutrino problem. Signatures of this solution are considered in details and confronted with experimental results. Recent theoretical developments - theories with low fundamental scale of quantum gravity and large extra dimensions - give new 'bulk - brane' mechanism of generation of neutrino mass. In this framework new solution of the solar neutrino problem is possible via resonance conversion of the electron neutrino in the bulk states. The solution implies that one of extra dimensions has the size about 0.1 mm