Involved in myo-inositol synthesis. Is a key enzyme in the phytic acid biosynthesis pathway in seeds. D-glucose 6-phosphate = 1D-myo-inositol 3-phosphate Polyol metabolism; myo-inositol biosynthesis; myo-inositol from D-glucose 6-phosphate: step 1/2. Highly expressed in anthers, but transcripts are undetectable in roots, leaves, flowers and embryos. Belongs to the myo-inositol 1-phosphate synthase family.