A paramutation phenomenon is involved in the genetics of maize low phytic acid1-241 (lpa1-241) trait

So far, in maize, three classes of mutants involved in phytic
acid biosynthesis have been isolated: lpa1, lpa2 and lpa3. In
2007, a gene tagging experiment performed by Shi et al.
found that mutations in ZmMRP4 (multidrug resistanceassociated
proteins 4) gene cause lpa1 phenotype. In
previous studies, we isolated and described a single
recessive lpa mutation (originally named lpa241), which
was allelic to the lpa1-1 mutant, and was consequently
renamed lpa1-241. It showed a decrease in the expression of
the myo-inositol (Ins)-3-phosphate synthase gene (mips1S).
In this study, we present genetic and molecular analyses of
the lpa1-241 mutation that indicate an epigenetic origin of
this trait, that is, a paramutagenic interaction that results in
meiotically heritable changes in ZmMRP4 gene expression,
causing a strong pleiotropic effect on the whole plant. The
use of a 5-Azacytidine treatment provided data suggesting
an association between gene methylation and the lpa1-241
phenotype. To our knowledge, this is the first report of a
paramutagenic activity not involving flavonoid biosynthesis in
maize, but regarding a key enzyme of an important metabolic
pathway in plants.