Mutation of a bHLH transcription factor allowed almond domestication

We report the completion of the almond reference genome. Map-based cloning using an F1 population segregating for kernel taste led to the identification of a 46-kilobase gene cluster encoding five basic helix-loop-helix transcription factors, bHLH1 to bHLH5. Functional characterization demonstrated that bHLH2 controls transcription of the P450 monooxygenase–encoding genes PdCYP79D16 and PdCYP71AN24, which are involved in the amygdalin biosynthetic pathway. A nonsynonymous point mutation (Leu to Phe) in the dimerization domain of bHLH2 prevents transcription of the two cytochrome P450 genes, resulting in the sweet kernel trait.

Source: ScienceNOW - June 12, 2019 Category: Science Authors: Sanchez-Perez, R., Pavan, S., Mazzeo, R., Moldovan, C., Aiese Cigliano, R., Del Cueto, J., Ricciardi, F., Lotti, C., Ricciardi, L., Dicenta, F., Lopez-Marques, R. L., Moller, B. L. Tags: Botany reports Source Type: news