Isolation and characterization of a novel anionic peroxidase cDNA found inpoplar (Populus nigra) suspension cultured cells

A cDNA clone from Populus nigra L. var. italica Koehne, denoted PCY2-6, cod ing for an anionic peroxidase has been isolated, cloned, and characterized. PCY2-6 is 1160bp long; and its deduced product, PnC26, contains 343 amino acid residues. The mature protein has a calculated isoelectric point of 4.0 9. The protein contains two motifs typical of peroxidase and 10 potential N -glycosylation sites. PnC26 is therefore classified as an anionic peroxidas e. The mRNA of the PCY2-6 gene family was detected in immature and mature l eaves and in two parts of current-year stems: the shoot tip and the older s tem. The mRNA of PCY2-6 gene family was found to localize in the phloem and cortex of the current-year stems. We therefore conclude that expression of the PCY2-6 gene family is related to bark development.