@article{mbs:/content/journal/micro/10.1099/mic.0.27346-0, author = "Casas-Flores, Sergio and Rios-Momberg, Mauricio and Bibbins, Martha and Ponce-Noyola, Patricia and Herrera-Estrella, Alfredo", title = "BLR-1 and BLR-2, key regulatory elements of photoconidiation and mycelial growth in Trichoderma atroviride", journal= "Microbiology", year = "2004", volume = "150", number = "11", pages = "3561-3569", doi = "https://doi.org/10.1099/mic.0.27346-0", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.27346-0", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = "In fungi, phototropism, the induction of carotenogenesis and reproductive structures, and resetting of the circadian rhythm are controlled by blue light. Trichoderma atroviride, a fungus used in biological control, sporulates in a synchronized manner following a brief pulse of blue light. Due to its apparent simplicity, this response was chosen for pursuing photoreceptor isolation. Two genes were cloned, blue-light regulators 1 and 2 (blr-1 and blr-2), similar to the Neurospora crassa white-collar 1 and 2, respectively. The BLR-1 protein has all the characteristics of a blue-light photoreceptor, whereas the structure of the deduced BLR-2 protein suggests that it interacts with BLR-1 through PAS domains to form a complex. Disruption of the corresponding genes demonstrated that they are essential for blue-light-induced conidiation. blr-1 and blr-2 were also shown to be essential for the light-induced expression of the photolyase-encoding gene (phr-1). Mechanical injury of mycelia was found to trigger conidiation of T. atroviride, a response not described previously. This response was not altered in the mutants. A novel effect of both red and blue light on mycelial growth was found involving another light receptor, which is compensated by the BLR proteins.", }