Phosphatase required for histidine production. Acts also on L-galactose 1-phosphate (L-Gal 1-P), D-myoinositol 3-phosphate (D-Ins 3-P) and D-myoinositol 1-phosphate (D-Ins 1-P). a myo-inositol phosphate + H2O = myo-inositol + phosphate H2O + L-histidinol phosphate = L-histidinol + phosphate beta-L-galactose 1-phosphate + H2O = L-galactose + phosphate Amino-acid biosynthesis; L-histidine biosynthesis; L-histidine from 5-phospho-alpha-D-ribose 1-diphosphate: step 8/9. Polyol metabolism; myo-inositol biosynthesis; myo-inositol from D-glucose 6-phosphate: step 2/2. Ubiquitous. High expression in roots. Expressed in pistil and seed endosperm. Expressed at all developmental stages. Detected in globular to heart stage embryos. Embryo lethality. No redundancy with IMPL1 or VTC4. Belongs to the inositol monophosphatase superfamily. Extended N-terminus. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus.