Pests find the tender young leaves of corn or rice plants tasty, spurning the less-palatable older leaves. By harnessing a gene influencing such age-related characteristics, researchers could have found a way to genetically manipulate crops to express protective traits, while avoiding the controversy surrounding the insertion of foreign genes or the use of pesticides. Tanya Berardini and colleagues at the University of Pennsylvania's Plant Science Institute (Philadelphia, PA) screened Arabidopsis thaliana seedlings for genetic mutations that accelerated the production and distribution of trichomes (glandular leaf hairs), which indicate a plant's maturity (Science 291, 2405–2407, 2001). The SQUINT (SQN) mutations identified generated plants with elliptical leaves—hence the “squinty-eyed” namesake—similar to mature leaves, but the plants flowered and produced seeds as normal. SQN encodes a protein related to bovine cyclophilin 40 (CyP40), which regulates specific cell-signaling pathways. Scott Poethig, co-author on the paper, says: “Our working hypothesis is that cyp40 regulates phase change by affecting the activity of one or more proteins specifically involved in this process. ... [However,] CyP40 may only be useful for truncating the expression of the juvenile phase, not prolonging it.” The function of CyP40 in plants is currently being investigated.