Life Science and Medical News from Around the Globe
Pineapple Genome Sequence and Evolution of Drought-Resistant CAM Photosynthesis
By sequencing its genome, scientists are homing in on the genes and genetic pathways that allow the juicy pineapple plant to thrive in water-limited environments. The new findings, reported online on November 2, 2015 in an open-access article in Nature Genetics, also open a new window on the complicated evolutionary history of grasses like sorghum and rice, which share a distant ancestor with pineapple. The Nature Genetics article is titled “The Pineapple Genome and the Evolution of CAM Photosynthesis.” Humans have cultivated pineapple for more than 6,000 years, beginning in present-day southwest Brazil and northeast Paraguay. Today, more than 85 countries produce about 25 million metric tons of pineapple fruit each year, with a gross production value approaching $9 billion. Like many plants, the ancestors of pineapple and grasses experienced multiple doublings of their genomes. Tracking the remnants of these "whole-genome duplications" in different plant species helps researchers trace their shared - and independent - evolutionary histories. "Our analysis indicates that the pineapple genome has one fewer whole genome duplication than the grasses that share an ancestor with pineapple, making pineapple the best comparison group for the study of cereal crop genomes," said University of Illinois Plant Biology Professor Ray Ming, Ph.D., who led the multi-institutional pineapple genome sequencing effort. The work uncovered evidence of two whole-genome duplications in the pineapple's history, and validated previous findings of three such duplications in grasses. Photosynthesis converts solar energy to chemical energy, allowing plants to build the tissues that sustain life on Earth.