DEVELOPMENTAL AND PHOTOREGULATION OF AL-1 AND AL-2, STRUCTURAL GENES FOR 2 ENZYMES ESSENTIAL FOR CAROTENOID BIOSYNTHESIS IN NEUROSPORA

The levels of al-1 and al-2 transcripts change dramatically in respons e to light and development during the formation of Neurospora crassa a sexual spores (conidia). al-1 and al-2 mRNAs accumulate throughout con idiation irrespective of lighting conditions initially at low levels. As conidiation proceeds, two increases in albino message accumulation are observed. This developmentally induced photoindependent message ac cumulation was not observed in Neurospora mutants blocked at relevant stages of conidiation. During conidiation, light induces additional ac cumulation of al-1 and al-2 gene-specific transcripts; the photoinduce d increase in albino gene transcript levels was not observed in two Ne urospora mutants, wc-1 and wc-2, that are defective in all physiologic al photoresponses. (C) 1995 Academic Press,Inc.