ZmG2
The full-length coding sequence of ZmG2 was amplified from cDNA of the maize accession B73. Each sequence was recombined into the pIX-HALO vector using LR Clonase II (Invitrogen). The HALO-ZmGLK1 and HALO-ZmG2 proteins were generated using 500 ng each of the pIX-HALO- ZmGLK1 and pIX-HALO- ZmG2 plasmids and the TNT SP6 Coupled Reticulocyte Lysate System (Promega) following the manufacturers protocol. The resulting proteins were immediately incubated with 10 L of Magne-HALOTag beads (Promega) for 1 h at 25 C in 1 phosphate-buffered saline (PBS) with 0.005% Nonidet P-40 and 0.1% Tween. Bound proteins were washed five times with PBS with 0.1% Tween (PBST), then digested with DNaseI. The DNA-free HALO-ZmGLK1 and HALO-ZmG2 proteins were then incubated with 500 g of ultrasonically-fragmented Nipponbare genomic DNA (200-800-bp fragments) for 1 h at 25 C. The beads were washed eight times with PBST, then elution buffer was added and the beads were incubated at 98 C for 10 min. Sequencing libraries were constructed from the eluted DNA using the TruePrep DNA Library Prep Kit V2 for Illumina (Vazyme).