Photoregulation of the Carotenoid Biosynthetic Pathway in Albino and White Collar Mutants of Neurospora crassa

Abstract

The conversion of isopentenyl pyrophosphate to phytoene in Neurospora crassa requires both a soluble and a particulate fraction. Soluble and particulate enzyme factions obtained from light-treated and dark-grown wid type, albino-i, alZbi-2, albino-3, and white collar-I strains were mixed in various combinations, and the activity for conversion of 11-'4Clisopen-tenyl pyrophosphate to phytoene was assayed. From such experiments it can be concluded that (a) albino-3 is defective in the soluble fraction; (b) albino-2 is defective in the particulate fraction; (c) the in vivo lght treatment increases the enzyme actvity in the particulate fraction; (d) this light effect occurs in wild type, albno-I, and albin-3 straiw and (e) enzyme activity is present in the particulate faction obtained from the white collar-i mutant, but the in vivo light treatment does not cause an increase in this activity. To measure directly the level of particulate enzyme activity,

A single gene for lycopene cyclase, phytoene synthase, and regulation of carotene biosynthesis in Phycomyces

“…5) to homologous genes from representatives of three major classes of Fungi, Zygomycetes (Mucor), Ascomycetes (Neurospora), and Basidiomycetes (Xanthophyllomyces). Gene al-2 from Neurospora, defined by albino mutations and responsible for phytoene synthase (40), was the first to be cloned and sequenced (31). A cyclase activity has been shown to be present in the amino-terminal domain of the al-2 gene product by the recent isolation of reddish mutants of Neurospora that carry mutations in that domain (J.A.…”

Reproduction without sex: conidiation in the filamentous fungus Trichoderma

“…Both BLR and WC proteins contain conserved Per-ARNT-Sim (PAS) domains, which have been shown to be involved in signal transduction through monitoring of the energy state of the cell, in protein-protein interactions and in the sensing of environmental signals (Möglich et al, 2009;Taylor & Zhulin 1999). In N. crassa, WC-1 and WC-2 (White Collar 1 and White Collar 2) mediate all known light responses (Ballario et al, 1996;Cheng et al, 2003;Degli-Innocenti & Russo, 1984;Froehlich et al, 2002;Harding & Turner, 1981;He et al, 2002;Herrera-Estrella & Horwitz, 2007;Linden & Macino, 1997). However, in T. atroviride, there appear to be both BLR-dependent and -independent blue-light perception pathways (Berrocal-Tito et al, 2000;CasasFlores et al, 2006;Rocha-Ramirez et al, 2002;Schmoll et al, 2010).…”

Nitrogen regulation of blue light-inducible genes in Neurospora crassa

“…The a1 genes are necessary for carotenoid production (Harding & Turner, 1981). al-1 encodes the enzyme phytoene dehydrogenase (Schmidhauser et al, 1990) Russo, 1986).…”