Polyploidy and gene dosage effects on peroxidase activity in ferns.

Abstract

Total soluble proteins, peroxidase, and peroxidase isozymes were examined in polyploid series of fern gametophytes and sporophytes. A distinctive pattern of protein bands was associated with gametophytes and sporophytes and the pattern did not vary within each phenotype with increases in the genome. Peroxidase activity per cell increased in direct proportion to increases in the genome and was determined to be gene dosage related. Slight differences in the patterns of peroxidase isozyme bands were associated with increases in the chromosome complement in both series of plants, but major variations were found between gametophyte and sporophyte. Quantitative analysis of peroxidase activity in each band revealed both increases and decreases in individual isozymes as ploidy increased. These findings suggest the involvement of regulatory mechanisms controlling isozyme activity.