Molecular characterization of 5' UTR of the () gene among exotic and indigenous inbreds for its utilization in maize biofortification.

Maize grains are the important source of food and energy, but possess very low proA (< 2.5 µg/g) compared to target level of 15 µg/g set by HarvestPlus to alleviate VAD. Favorable allele having variation in 5' untranslated region (UTR) of () gene enhances concentration of proA in maize. To identify the sequence variation in 5' UTR of , a set of diverse 13 inbreds of indigenous and exotic origin was characterized for allelic constitution of . Inbreds possessed wide variation in proA (1.62-23.12 µg/g) with a mean of 9.64 µg/g. The proA in CIMMYT-HarvestPlus genotypes having favorable allele of was very high (22.28 µg/g), whereas the Indian inbreds with the same allele possessed very low proA (2.48 µg/g). Eight genotypes viz., HKI161, HKI163, HKI161-PV, HKI163-PV, HKI193-1-PV, HKI193-2-PV, HP704-22 and HP704-23 revealed the presence of favorable allele, while VQL1, DMRIL47, MGU-PV-123/C6, HKI193-1 and HKI193-2 showed the presence of unfavorable allele of gene. Sequence comparison of favorable allele of Indian (HKI161 and HKI163) and exotic genotypes (HP704-22 and HP704-23) revealed seven having three transitions ( and : G to A, : C to T) and four transversions (: C to G, : T to G, : G to C and : G to T). Four (: position 446, : position 458, : position 459 and : position 483) discriminated the low- and high- proA lines having favorable allele of . These hold significance in enrichment of proA in maize for marker development and their use in marker-assisted selection.