biostudies-literatureUnknown74(1)Friedl MAHypocrea atroviridis is frequently used as a photomorphogenetic model due to its ability to conidiate upon exposure to light. Light is thereby believed to be the primary trigger for spore formation. In contrast, we show here that conidiation is primarily carbon source dependent and that illumination plays a catalytic role; of a total of 95 tested carbon sources, only a small set of carbohydrates, polyols, and sugar acids allowed conidiation in darkness, and on most of them, conidiation was significantly more strongly expressed in light. In addition, there are also a number of carbon sources on which H. atroviridis conidiates in darkness, but light does not further stimulate the process. Yet on another small set of carbon sources (L-sorbitol, D-fucose, D- and L-arabinose, and erythritol), HApplied and environmental microbiology245-50https://www.ebi.ac.uk/biostudies/studies/S-EPMC2223218biostudies-literatureCarbon source dependence and photostimulation of conidiation in Hypocrea atroviridis.PMC2223218Friedl MADruzhinina ISKubicek CPfalseCarbon source dependence and photostimulation of conidiation in Hypocrea atroviridis.Hypocrea atroviridis is frequently used as a photomorphogenetic model due to its ability to conidiate upon exposure to light. Light is thereby believed to be the primary trigger for spore formation. In contrast, we show here that conidiation is primarily carbon source dependent and that illumination plays a catalytic role; of a total of 95 tested carbon sources, only a small set of carbohydrates, polyols, and sugar acids allowed conidiation in darkness, and on most of them, conidiation was significantly more strongly expressed in light. In addition, there are also a number of carbon sources on which H. atroviridis conidiates in darkness, but light does not further stimulate the process. Yet on another small set of carbon sources (L-sorbitol, D-fucose, D- and L-arabinose, and erythritol), H2008-01-01T00:00:00Z2008 Jan2026-05-29T16:43:10.234Z2019-03-27T02:43:54ZS-EPMC22232181798194810.1128/aem.02068-0710.1128/AEM.02068-07