Transition from real to virtual polarized photon structures

We investigate the transition of the polarized photon structure function g1γ(x,Q2,P2) when the target photon shifts from on-shell (P2=0) to far off-shell (P2≫Λ2) region. The analysis is performed to the next-to-leading order in QCD. The first moment of g1γ which vanishes for the real photon, turns to be a negative value when target photon becomes off-shell. The explicit P2-dependence of the first moment sum rule as well as of the structure function g1γ(x,Q2,P2) as a function of x is studied in the framework of the vector meson dominance model.