Myo-inositol 1-phosphate synthase (MIPS) is a pivotal
enzyme that initiates the first step of phytic acid synthesis.
In the present study the MIPS-1s gene isolated was from an
inbred line of maize Qi319 containing low contents of phytic
acid (lpa). Its sequence and expression patterns were also
characterized. Results showed that the full-length genomic
DNA sequence of the MIPS-1s gene is comprised of ten
exons and nine introns, with a length of 3596 bp, and an
open reading frame of 1533 bp that encodes a protein with
510 amino acids. A single amino acid substitution was
found, compared to the sequence of the inbred maize line
B73. In silico promoter analysis revealed various ciselements
that might contribute to the differential regulation
of MIPS-1s. The expression patterns of MIPS-1s proteins in
leaves, roots, flowers and developing seeds of maize were
also investigated using western blot. It showed similar
patterns compared to the control line (Chang 7-2),
suggesting that the MIPS-1s protein plays similar roles in
the process of maize development and growth. Notably, it
was found that the control line had a dramatically higher
abundance of MIPS-1s protein than did Qi319, in the
developing seeds and especially during the early period.
This strongly indicates that higher levels of MIPS expression
should precede and/or accompany synthesis and
accumulation of phytate.
Keywords: Maize, myo-inositol 1-phosphate synthase (MIPS), low phytic acid (LPA), western blot (WB), expression
Year: 2015
Volume: 75
Issue: 4
Article DOI: 10.5958/0975-6906.2015.00074.7
Print ISSN: 0019-5200
Online ISSN: 0975-6906
Qinghua Gao info_circle
Cui Zhang, Wei Fan, Dongdong Niu, Ruijuan Rong, Xu info_circle