It was shown previously that when a chromosomal Spore killer factor is heterozygous in Neurospora species with eight-spored asci, the four sensitive ascospores in each ascus die and the four survivors are all killers. Sk-2K and Sk-3K are nonrecombining haplotypes that segregate with the centromere of linkage group III. No killing occurs when either one of these killers is homozygous, but each i...

Neurospora crassa has a long history as an excellent model for genetic, cellular, and biochemical research. Although this fungus is known as a saprotroph, it normally appears on burned vegetations or trees after forest fires. However, due to a lack of experimental evidence, the nature of its association with living plants remains enigmatic. Here we report that Scots pine (Pinus sylvestris) is a...

Two morphologically distinctive slow growing strains of Neurospora crassa have been isolated and studied. These, abn-1 and abn-2, differ from wild type in that their growth rates are greatly reduced and often irregular, aerial hyphae are absent, conidia are extremely rare, and no protoperithecia are formed. Growth was not improved by addition of any nutrients tested, oxygen consumption was simi...

Transfer ribonucleic acid (tRNA) methylases were studied during the germination of spores in Neurospora crassa. The total methylase capacity and base specific tRNA methylase activities were determined in extracts from cells harvested at various stages of germination. Germinated conidia have a 65% higher methylase capacity than ungerminated conidia. Three predominant methylase activities were fo...

Heterotrimeric (αβγ) G proteins are crucial components of eukaryotic signal transduction pathways. G-protein-coupled receptors (GPCRs) act as guanine nucleotide exchange factors (GEFs) for Gα subunits. Recently, facilitated GDP/GTP exchange by non-GPCR GEFs, such as RIC8, has emerged as an important mechanism for Gα regulation in animals. RIC8 is present in animals and filamentous fungi, such a...

This is an opportune time to evaluate the contributions of Neurospora to genetics and biology in the recent past and to anticipate what its role might be in the years ahead. The turn of the century marks the 75th anniversary of the first genetic experiments with Neurospora. Although hisorical accounts of Neurospora genetics usually begin with the 1941 paper of Beadle and Tatum, genetic analysis...

HIS study of interallelic recombination was originally initiated to compare Tthe recombination and complementation maps of the me-2 gene of Neurospora crassa (MURRAY 1960b). Methionine-independent progeny from crosses between me-2 alleles were classified with respect to the markers which were present on both sides of the me-2 gene. One of the two classes of methionine prototrophs having markers...

BACKGROUND WHITE COLLAR-1 (WC-1) mediates interactions between the circadian clock and the environment by acting as both a core clock component and as a blue light photoreceptor in Neurospora crassa. Loss of the amino-terminal polyglutamine (NpolyQ) domain in WC-1 results in an arrhythmic circadian clock; this data is consistent with this simple sequence repeat (SSR) being essential for clock f...

The filamentous fungus Neurospora crassa produces three types of spores by using different developmental pathways: macroconidiation, microconidiation, and sexual spore (ascospore) formation. Several genes of unknown function have been cloned by virtue of their expression during macroconidiation but not during mycelial growth (con genes). It had been postulated that expression of the con genes w...

At first, the saprophytic eukaryote Neurospora crassa and the photosynthetic prokaryote Synechococcus elongatus may seem to have little in common. However, in both organisms a circadian clock organizes cellular biochemistry, and each organism lends itself to classical and molecular genetic investigations that have revealed a detailed picture of the molecular basis of circadian rhythmicity. In t...