biologia plantarum

Biologia plantarum 56:441-450, 2012 | DOI: 10.1007/s10535-012-0114-2

Isolation and molecular characterization of cinnamate 4-hydroxylase from apricot and plum

A. Pina^1,*, T. Zhebentyayeva², P. Errea¹, A. Abbott²

¹ Unidad de Fruticultura, CITA de Aragón, Zaragoza, Spain

² Department of Genetics and Biochemistry, Clemson University, Clemson, USA

Cinnamate 4-hydroxylase (C4H) is the second enzyme in the phenylpropanoid pathway which participates in the synthesis of numerous phenylpropanoid compounds such as flavonoids, lignins, suberins and others. We identified a gene putatively coding for Class I C4H in apricot and plum and we analyzed the expression pattern of this gene under different apricot/plum graft combinations with different degree of compatibility. The full-length cDNA is 1 739 bp with a 1 515 bp open reading frame encoding a protein of 504 amino acids. Like other C4Hs, the predicted C4H polypeptides included conserved domains of cytochrome P₄₅₀. The genomic sequence of the apricot C4H gene was interrupted by two introns 335 bp and 904 bp long. Several regulatory motifs including P-, A-, L- and H-boxes, which were conserved across phenylpropanoid metabolism-related genes in higher plants, were found in a 1 300 bp upstream promoter region of the apricot C4H gene. A phylogenetic analysis showed that all Prunus sequences clustered together and were closely related to Malus and Rubus C4H genes. The transcription of Class I PruC4H was detected in all the examined graft combinations, which suggested its rather constitutive character.

Keywords: fruit trees; full length cDNA; graft compatibility; phenylpropanoid pathway; promoter analysis

Subjects: full length cDNA; graft compatibility; phenylpropanoid pathway; promoter analysis; cinnamate 4-hydroxylase; PCR; Southern blot; RACE; amino acid sequence; phylogenetic tree

Received: May 21, 2010; Accepted: June 10, 2011; Published: September 1, 2012  Show citation