The full-length sequence of OsMAX1e was acquired
through the amplification of Nipponbare DNA. The
coding regions of OsMAX1a were also acquired
through the amplification of Nipponbare cDNA. Then
the DNA fragments of OsMAX1e and OsMAX1a were
connected to pEASYTM-T1 Simple-Cloning Vector
(TransGene), respectively. The correct recombinant
plasmids T1-OsMAX1a and T1-OsMAX1e were
confirmed by sequencing. T1-OsMAX1a and pHB were
connected after being digested by Xba I and Sac I
restriction endonucleases. Meanwhile, T1-OsMAX1e
and pHB were digested by Xba I and Hind III
restriction endonucleases before connecting. Ultimately,
we constructed the vectors pHB-OsMAX1a and
pHB-OsMAX1e driven by the 35S promoter.
The 400 bp mRNA sequences were used to construct
the RNA interference vectors RNAi-OsMAX1a and
RNAi-OsMAX1e. Because OsMAX1 has multiple
copies, the conservative sequence of OsMAX1a was
also selected to design another RNAi fragment, i.e.,
RNAi-OsMAX1CON. All RNAi-OsMAX1-sense
sequences were acquired through the amplification of
Nipponbare cDNA (the primer sequences are shown in
Table 2). RNAi-OsMAX1-sense was digested by Sal I
and Hind III restriction endonucleases and then
connected with the vector pSK-int to generate
intermediate vector pSK-Sense. RNAi-antisense was
digested by CoR I/Sac I restriction endonucleases and
then connected with the pSK-Sense vector to construct
pSK-RNAi. Two pSK-RNAi vectors pSK-OsMAX1a
-RNAi and pSK-OsMAX1e-RNAi were generated.
The reconstructed plasmid pSK-RNAi was digested
with Sal I and Sac I restriction endonucleases and the
1 kb segments were recycled for RNAi. Connecting
the purified RNAi clips with pOsAct2-1-nos, we got
the recombinant plasmids OsMAX1a-RNAi and
OsMAX1e-RNAi, and further validated with Sal I and
Sac I restriction endonucleases. The construction of
interference vector and the structure of pHB-OsMAX1
are showed in Supplemental Fig. 3.