Plant materials and growth conditions
The rice cultivar Nip, rice blast susceptible cultivar LTH,Pik-H4 NILs in LTH background were used for constructing transgenic plants and inoculation assays. TheRFP ::PPik-H4 ::GFP /Nip, PPik1-H4 ::GUS/Nip and PPik2-H4 ::GUS/Nip were used for expression pattern analysis of Pik-H4 . The OE-Pik1-H4 -GFP /Pik and OE-Pik2-H4 -GFP /Pik were generated by crossing OE-Pik1-H4 -GFP /LTH and OE-Pik2-H4 -GFP /LTH with Pik-H4 NILs respectively. Nip was also used for protoplast transformation to identify bidirectional promoter activity. Nicotiana benthamianawas used for agroinfiltration to evaluate promoter activity and HR assays.
Rice cultivars grew on soil in a greenhouse with a natural light cycle and 30°C/light, 26°C/dark. Tobacco seeds were germinated in MS medium and transferred to the soil after germination in a growth chamber with a 16-h/8-h light/dark cycle at 24°C.