Natural GMOs Part 150. Tomato flavor was helped along by a 'jumping gene'

Taken by fir0002 | flagstaffotos.com.au

Rosie Mestel at the LA Times is on cue with GMOs:

...Now the Florida scientists have discovered a DNA change that contributes to this red-green flavor difference. Sometime during the evolution of red tomato species, a piece of DNA -- a so-called “jumping gene”-- inserted itself right next to a key flavor gene, ramping up its activity.  As a result, the esters are destroyed in greater amounts in red tomatoes compared with green as the fruit begins to ripen.
Charles Goulet and coauthors note in their paper in the Proceedings of the National Academy of Sciences  that findings like this might help researchers figure out how to breed tomatoes that taste better...  

@ Tomato flavor was helped along by a 'jumping gene' - latimes.com:


Role of an esterase in flavor volatile variation within the tomato clade


Charles Goulet, Melissa H. Mageroy, Nghi B. Lam, Abbye Floystad, Denise M. Tieman, and Harry J. Klee
+ Author Affiliations

Horticultural Sciences Department, University of Florida, Gainesville, FL 32611
Contributed by Harry J. Klee, September 21, 2012 (sent for review July 13, 2012)

Abstract

Tomato flavor is dependent upon a complex mixture of volatiles including multiple acetate esters. Red-fruited species of the tomato clade accumulate a relatively low content of acetate esters in comparison with the green-fruited species. We show that the difference in volatile ester content between the red- and green-fruited species is associated with insertion of a retrotransposon adjacent to the most enzymatically active member of a family of esterases. This insertion causes higher expression of the esterase, resulting in the reduced levels of multiple esters that are negatively correlated with human preferences for tomato. The insertion was evolutionarily fixed in the red-fruited species, suggesting that high expression of the esterase and consequent low ester content may provide an adaptive advantage in the ancestor of the red-fruited species. These results illustrate at a molecular level how closely related species exhibit major differences in volatile production by altering a volatile-associated catabolic activity.

Published online before print October 29, 2012, doi: 10.1073/pnas.1216515109
PNAS October 29, 2012