Scaling relations of HI mass, stellar mass and SFR for galaxies in three classes of increasing Def_HI blue: Def_HI ≤ 0.3 (normal); green: 0.3 < Def_HI < 0.9 (perturbed), red: Def_HI ≥ 0.9 (highly perturbed). Symbols are assigned according to the morphology. E-S0-S0a: circles; giant spirals (Sa-Sm): squares; Irr-BCD: triangles; AGN: asterisks. Panel a): gas fraction (M_HI/M_∗) versus M_∗. The diagonal dot-dashed line represents the limiting sensitivity of ALFALFA at the distance of Virgo. The black symbols give the representative – sample extracted from GASS by Catinella et al. (2010), the large magenta squares represent the HI-normal sample and the large red squares the Virgo sample from Cortese et al. (2011). Across the stellar mass range in common there is an almost perfect agreement, but the present sample extends the correlation to two orders of magnitude fainter. Panel b): SFR versus M_∗. Panel c): specific SFR versus M_∗. The blue and red solid lines reproduce the relations plotted in Fig. 8 of Schiminovich et al. (2010) for the star-forming sequence (blue) and the non-star forming locus of red galaxies (red).