Photostimulation of conidiation in mutants of Neurospora crassa.
Various mutants of Neurospora crassa were screened for light-stimulated conidiation which is a blue light effect and, at least in strain albino-band, is mediated by the flavoprotein nitrate reductase (NR). NR- mutants showed practically no photoconidiation under standard conditions. However, in fusion products of nit-1 (diaphorase activity present, terminal activity missing) plus nit-3 (terminal activity present, diaphorase activity missing), NR activities and photoconidiation were partially restored. Mutants with altered light sensitivities, such as white collar WC-1 and light-insensitive lis-2 and lis-3, had normal NR activities and their conidiation was promoted by light, whereas WC-2 and lis-1 responded only slightly. These two mutants showed low NR activities especially when grown on solid medium which might be the cause of their blindness. Experiments with NR- mutants indicated that nitrite reductase might also act as a blue light photoreceptor.
Ninnemann
H
H
Institut für Chemische Pflanzenphysiologie der Universität Tübingen, F.R.G.
D003624:Darkness; D008027:Light; D009154:Mutation; D009492:Neurospora crassa / Q000235:genetics / Q000254:growth & development / Q000528:radiation effects*; D050901:Nitrate Reductase; D009565:Nitrate Reductases / Q000235:genetics; D013172:Spores, Fungal / Q000235:genetics / Q000528:radiation effects
D009565:Nitrate Reductases; D050901:Nitrate Reductase