Microarray comparative analysis of wild-type and hd1-3 mutant rice

Heading date1(Hd1) is a critical regulator controlling rice flowering time, which promotes flowering under short-day (SD) conditions and represses flowering under long-day (LD) conditions. In our previous study (Luan et al., 2009), we identified a rice mutant, hd1-3, in which the Hd1 gene was deficient due to several insertions/deletions in the coding region. To search for downstream genes regulated by Hd1, we performed microarray analysis of hd1-3 mutant and the wild-type Zhonghua11 under both SD and LD conditions. According to the microarray results, SDG712 gene was significantly downregulated in the hd1-3 mutant, indicating that SDG712 gene may acts downstream of Hd1, and may functions in rice flowering time regulation. The leaves of 35-day-old plants of hd1-3 mutant and the wild-type Zhonghua11 grown under SD and LD conditions were collected. Total RNAs were extracted using TRIzol and mRNAs were purified for microarray analysis.