"The duplication contributed to adding additional members of gene families that are involved in regulating important kiwifruit characteristics, such as fruit vitamin C, flavonoid and carotenoid metabolism," says Fei.
For the sequencing, the scientists used a Chinese variety called "Hongyang," which is widely grown in China, to produce the draft sequence. They then compared kiwifruit to the genomes of other representative plant species including tomato, rice, grape and the mustard weed Arabidopsis. They uncovered about 8,000 genes that were common among all five species. The comparison revealed important evolutionary relationships, including the development genes related to fruit growth, ripening, nutrient metabolism, and disease resistance.
Prior to the study, extensive research on the metabolic accumulation of vitamin C, carotenoids and flavonoids had been reported in kiwifruits, but genome sequence data, critical for its breeding and improvement, had never been available.
"The kiwifruit genome sequence represents the first of a member in the order Ericales, thus providing a valuable resource for comparative genomics and evolutionary studies," Fei says. "We expect to continue generating genome sequences from other kiwifruit varieties to investigate the genetic diversity of kiwifruit and elucidate regulatory networks of important biological processes."
The sequence is accessible online at the Kiwifruit Genome Database.
|Contact: Melissa Osgood|