cDNA-AFLP analysis on transcripts associated with hydroxysafflor yellow A(HSYA) biosynthetic pathway in Carthamus tinctorius

Hydroxysafflor yellow A (HSYA), an important active compound, is uniquely present in florets of Carthamus tinctorius. In current study, we applied cDNA amplified fragment length polymorphism (cDNA-AFLP) to screen genes expressed differently between plants with and without HSYA. One hundred and thirty-two primer combinations produced 6751 fragments, seven transcript-derived fragments (TDFs) showed consistent difference between two gene pools. An independent RT-PCR expression analysis validated the expression pattern for 3 TDFs (TDF-8, TDF-9 and TDF-27). The 3 TDFs were only transcripted in plants that contained HSYA, implying that they were associated with the formation of HSYA. In addition, a full length of TDF-8 was achieved, which termed as WV-prl. Bioinformatics analysis showed that it carried a sequence highly homologous to the Broad bean wilt virus. Our study revealed that the three genes are involved in the process of response to some virus infection and functioning in HSYA production.