scholarly journals Cooperation among germinating spores facilitates the growth of the fungus, Neurospora crassa

2012 ◽  
Vol 8 (3) ◽  
pp. 419-422 ◽  
Author(s):  
F. Richard ◽  
N. L. Glass ◽  
A. Pringle
Keyword(s):  
Neurospora Crassa ◽  
Marine Invertebrates ◽  
Genetic Model ◽  
Life Forms ◽  
Wild Type ◽  
Mutant Strains ◽  
Net Benefits ◽  
Petri Dishes ◽  
Spore Densities

Fusions between individuals are a common feature of organisms with modular, indeterminate life forms, including plants, marine invertebrates and fungi. The consequences of fusion for an individual fungus are poorly understood. We used wild-type and fusion mutant strains of the genetic model Neurospora crassa to chronicle the fitness in two different laboratory habitats, and in each experiment started colonies from multiple different densities of asexual spores. On round Petri dishes, fusion enabled wild-type colonies to grow larger than mutant ( soft ) colonies; but in linear ‘race tubes’, the soft mutant always grew more quickly than the wild-type. Starting a colony with more spores always provided an advantage to a wild-type colony, but was more often neutral or a cost to the soft mutant. The ability to fuse does not provide a consistent advantage to wild-type colonies; net benefits are shaped by both habitat and initial spore densities.

scholarly journals Adenosine kinase-deficient mutant of Neurospora crassa

1982 ◽  
Vol 152 (3) ◽  
pp. 1292-1294
Author(s):  
J M Magill ◽  
P Dalke ◽  
T S Lyda ◽  
C W Magill
Keyword(s):  
Neurospora Crassa ◽  
Resistant Mutant ◽  
Adenosine Kinase ◽  
Deficient Mutant ◽  
Wild Type ◽  
Purine Nucleotides ◽  
Mutant Strains

Tubercidin-resistant mutant strains of Neurospora crassa were isolated, and at least one appeared to be deficient in adenosine kinase. No significant differences in [8-14C]adenosine labeling of purine nucleotides or nucleosides were found between the wild type and the adenosine kinase-deficient strains.

Glutamate synthase levels in Neurospora crassa mutants altered with respect to nitrogen metabolism

1981 ◽  
Vol 1 (2) ◽  
pp. 158-164
Author(s):  
N S Dunn-Coleman ◽  
E A Robey ◽  
A B Tomsett ◽  
R H Garrett
Keyword(s):  
Neurospora Crassa ◽  
Glutamate Dehydrogenase ◽  
Nitrogen Metabolism ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Glutamate Synthase ◽  
Wild Type ◽  
Mutant Strains ◽  
Synthase Regulation ◽  
Glutamate Biosynthesis ◽  
Glutamine Limitation

Glutamate synthase catalyzes glutamate formation from 2-oxoglutarate plus glutamine and plays an essential role when glutamate biosynthesis by glutamate dehydrogenase is not possible. Glutamate synthase activity has been determined in a number of Neurospora crassa mutant strains with various defects in nitrogen metabolism. Of particular interest were two mutants phenotypically mute except in an am (biosynthetic nicotinamide adenine dinucleotide phosphate-glutamate dehydrogenase deficient, glutamate requiring) background. These mutants, i and en-am, are so-called enhancers of am; they have been redesignated herein as en(am)-1 and en(am)-2, respectively. Although glutamate synthase levels in en(am)-1 were essentially wild type, the en(am)-2 strain was devoid of glutamate synthase activity under all conditions examined, suggesting that en(am)-2 may be the structural locus for glutamate synthase. Regulation of glutamate synthase occurred to some extent, presumably in response to glutamate requirements. Glutamate starvation, as in am mutants, led to enhanced activity. In contrast, glutamine limitation, as in gln-1 mutants, depressed glutamate synthase levels.

scholarly journals Glutamate synthase levels in Neurospora crassa mutants altered with respect to nitrogen metabolism.

1981 ◽  
Vol 1 (2) ◽  
pp. 158-164 ◽  
Author(s):  
N S Dunn-Coleman ◽  
E A Robey ◽  
A B Tomsett ◽  
R H Garrett
Keyword(s):  
Neurospora Crassa ◽  
Glutamate Dehydrogenase ◽  
Nitrogen Metabolism ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Glutamate Synthase ◽  
Wild Type ◽  
Mutant Strains ◽  
Synthase Regulation ◽  
Glutamate Biosynthesis ◽  
Glutamine Limitation

Glutamate synthase catalyzes glutamate formation from 2-oxoglutarate plus glutamine and plays an essential role when glutamate biosynthesis by glutamate dehydrogenase is not possible. Glutamate synthase activity has been determined in a number of Neurospora crassa mutant strains with various defects in nitrogen metabolism. Of particular interest were two mutants phenotypically mute except in an am (biosynthetic nicotinamide adenine dinucleotide phosphate-glutamate dehydrogenase deficient, glutamate requiring) background. These mutants, i and en-am, are so-called enhancers of am; they have been redesignated herein as en(am)-1 and en(am)-2, respectively. Although glutamate synthase levels in en(am)-1 were essentially wild type, the en(am)-2 strain was devoid of glutamate synthase activity under all conditions examined, suggesting that en(am)-2 may be the structural locus for glutamate synthase. Regulation of glutamate synthase occurred to some extent, presumably in response to glutamate requirements. Glutamate starvation, as in am mutants, led to enhanced activity. In contrast, glutamine limitation, as in gln-1 mutants, depressed glutamate synthase levels.

Transformation of Neurospora crassa with the cloned am (glutamate dehydrogenase) gene

1984 ◽  
Vol 4 (1) ◽  
pp. 117-122
Author(s):  
J A Kinsey ◽  
J A Rambosek
Keyword(s):  
Neurospora Crassa ◽  
Glutamate Dehydrogenase ◽  
Plasmid Vector ◽  
Wild Type ◽  
Mendelian Segregation ◽  
Dehydrogenase Gene ◽  
Mutant Strains ◽  
Colonial Morphology ◽  
Relationship Of ◽  
Lambda Dna

We used DNA containing the am gene of Neurospora crassa, cloned in the lambda replacement vector lambdaL-47 (this clone is designated lambdaC-10), and plasmid vector subclones of this DNA to transform am deletion and point mutant strains. By means of subcloning, all sequences required for transformation to am prototrophy and expression of glutamate dehydrogenase have been shown to reside on a 2.5-kilobase BamHI fragment. We also characterized several am+ strains that were obtained after transformation with lambdaC-10. These strains showed Mendelian segregation of the am+ gene, although less than 50% of the transformed strains showed the normal linkage relationship of am with inl. In all cases tested, the strains had incorporated lambda DNA as well. The lambda DNA also showed a Mendelian segregation pattern. In one case, the incorporation of am DNA in a novel position was associated with a mutagenic event producing a strain with a very tight colonial morphology. In all cases in which the am+ gene had become the resident of a new chromosome, glutamate dehydrogenase was produced to only 10 to 20% of the wild-type levels.

Polyene antibiotic affinities for the sterols of resistant and sensitive strains of Neurospora crassa

1977 ◽  
Vol 23 (1) ◽  
pp. 113-115 ◽  
Author(s):  
D. Johnson ◽  
R. Subden
Keyword(s):  
Candida Albicans ◽  
Neurospora Crassa ◽  
Resistant Mutant ◽  
Wild Type ◽  
Polyene Antibiotic ◽  
Polyene Antibiotics ◽  
Mutant Strains ◽  
Resistant Strains

Ergosterol, the principle sterol of many wild-type Neurospora and other Ascomycetes, had a greater affinity for polyene antibiotics than did lichesterol or eburicol, the sterols of some resistant mutant strains. The affinity was demonstrated by comparing the sterols extracted from sensitive and resistant strains of Neurospora crassa and Candida albicans for protection against polyene inhibition of sensitive N. crassa and for their ability to alter specific polyene absorption maxima.

scholarly journals INTRACELLULAR CRYSTALLINE ERGOSTEROL IN NEUROSPORA

1961 ◽  
Vol 11 (1) ◽  
pp. 171-177 ◽  
Author(s):  
Seizo Tsuda ◽  
E. L. Tatum
Keyword(s):  
Spectral Analysis ◽  
Fine Structure ◽  
Neurospora Crassa ◽  
Differential Centrifugation ◽  
Wild Type ◽  
Crystalline Inclusions ◽  
Cytochemical Analysis ◽  
Mutant Strains ◽  
Electron Microscopes

In the fungus Neurospora crassa, hexagonal crystalline inclusions have been observed with both the light and electron microscopes. These crystals have been enriched by differential centrifugation and found to be identical with ergosterol by the criteria of ultraviolet spectral analysis and cytochemical analysis. Observations have been made on the distribution and fine structure of the crystalline bodies in various wild type and mutant strains of N. crassa.

scholarly journals Mutants With Altered Sensitivity to a Calmodulin Antagonist Affect the Circadian Clock in Neurospora crassa

Genetics ◽  
1996 ◽  
Vol 143 (3) ◽  
pp. 1175-1180 ◽  
Author(s):  
Sakura Suzuki ◽  
Satoshi Katagiri ◽  
Hideaki Nakashima
Keyword(s):  
Neurospora Crassa ◽  
Period Length ◽  
Phase Shifting ◽  
Wild Type ◽  
Inhibitory Effects ◽  
Calmodulin Antagonist ◽  
Mutant Strains ◽  
In The Wild ◽  
Altered Sensitivity ◽  
Clock Mechanism

Abstract Two newly isolated mutant strains of Neurospora crassa, cpz-1 and cpz-2, were hypersensitive to chlorpromazine with respect to mycelial growth but responded differently to the drug with respect to the circadian conidiation rhythm. In the wild type, chlorpromazine caused shortening of the period length of the conidiation rhythm. Pulse treatment with the drug shifted the phase and inhibited light-induced phase shifting in Neurospora. By contrast to the wild type, the cpz-2 strain was resistant to these inhibitory effects of chlorpromazine. Inhibition of cpz-2 function by chlorpromazine affected three different parameters of circadian conidiation rhythm, namely, period length, phase and light-induced phase shifting. These results indicate that the cpz-2 gene must be involved in or related closely to the clock mechanism of Neurospora. By contrast, the cpz-1 strain was hypersensitive to chlorpromazine with respect to the circadian conidiation rhythm.

scholarly journals Transformation of Neurospora crassa with the cloned am (glutamate dehydrogenase) gene.

1984 ◽  
Vol 4 (1) ◽  
pp. 117-122 ◽  
Author(s):  
J A Kinsey ◽  
J A Rambosek
Keyword(s):  
Neurospora Crassa ◽  
Glutamate Dehydrogenase ◽  
Plasmid Vector ◽  
Wild Type ◽  
Mendelian Segregation ◽  
Dehydrogenase Gene ◽  
Mutant Strains ◽  
Colonial Morphology ◽  
Relationship Of ◽  
Lambda Dna

We used DNA containing the am gene of Neurospora crassa, cloned in the lambda replacement vector lambdaL-47 (this clone is designated lambdaC-10), and plasmid vector subclones of this DNA to transform am deletion and point mutant strains. By means of subcloning, all sequences required for transformation to am prototrophy and expression of glutamate dehydrogenase have been shown to reside on a 2.5-kilobase BamHI fragment. We also characterized several am+ strains that were obtained after transformation with lambdaC-10. These strains showed Mendelian segregation of the am+ gene, although less than 50% of the transformed strains showed the normal linkage relationship of am with inl. In all cases tested, the strains had incorporated lambda DNA as well. The lambda DNA also showed a Mendelian segregation pattern. In one case, the incorporation of am DNA in a novel position was associated with a mutagenic event producing a strain with a very tight colonial morphology. In all cases in which the am+ gene had become the resident of a new chromosome, glutamate dehydrogenase was produced to only 10 to 20% of the wild-type levels.

Sign in / Sign up

Export Citation Format

Share Document