02 August 2002
Vol 297, Issue 5582

About The Cover

Cover image expansion

COVER Normal and mutant strains of Neurospora crassa, a fungus that normally produces orange carotenoids (thought to provide protection from ultraviolet rays) in response to light. Deletion of the photoreceptor White Collar-1 blinds the fungus so that it fails to produce carotenoids, resulting in a white appearance. Loss of Vivid protein, a repressor of light-regulated processes, results in carotenoid overproduction and intense orange coloration. 815 [Image: C. Heintzen and A. Froehlich]