Figure 1.

Phenotypic Analysis of the gpa4-1 Mutant.

(A) Transverse sections of representative wild-type (Indica variety 9311) and gpa4-1 mutant dry seeds. Bar = 1 mm.

(B) and (C) Scanning electron microscopy images of transverse sections of wild-type (B) and gpa4-1 mutant (C) seeds. Bars = 10 μm.

(D) The 1000-grain weight of the wild type and gpa4-1. Values are mean ± sd. **P < 0.01 (n = 3, Student’s t test).

(E) SDS-PAGE profiles of total proteins of dry seeds from the wild type and the gpa4-1 mutant. pGlu, 57-kD proglutelins; αGlu, 40-kD glutelin acidic subunits; α-Glb, 26-kD α-globulin; βGlu, 20-kD glutelin basic subunits; Pro, prolamins.

(F) Immunoblot analysis of seed storage proteins using antiglutelin and anti-α-globulin antibodies. Blue triangles indicate the 57-kD proglutelins. Hollow arrows denote the glutelin acidic subunits (black) and basic subunits (red) in (F) and (G).

(G) Immunoblot analysis of the major glutelin subfamily proteins (i.e., GluA and GluB) and VPE1. Arrows indicate different forms of VPE1. pV, VPE1 precursor; iV, intermediate VPE1; mV, mature VPE1. EF-1α was used as a loading control in (F) and (G).