FGSC #5847

Mutant Type

Genus: N

reporting_genes: arg-3 his-3 nic-2 al-1;cot-1;pan-2

species: Neurospora crassa

allele: 30300 1710 43002 1-234-471;C102(t);1-153-96

stock: 74-OR271-53a

glasgow:

mutagen:

Depositor: FJD

Link Group: IL IR R R;IVR;VIR

MT: a

Species No: 10

gene_back: SL

oppmt: 0

trans:

ref1:

ref2:

site:

country:

ksudc_link: https://digital.lib.k-state.edu/item/neurospora-crassa/fgsc-5847

ksudc_link_html: https://digital.lib.k-state.edu/item/neurospora-crassa/fgsc-5847 ↗

Genes

Locus	Cultural Requirements	Link Group	Type
arg-3	Uses citrulline or arginine.	IL	B
cot-1	IVR. Between pan-1 (2%) and his-4 (1 to 6%) (692, 812, 816). Extremely colonial at 34°C, but completely normal growth, morphology, and fertility at 25°C and below. Linear growth is maximum at 24°C (374). Becomes colonial at 32°C; colonies from ascospores or conidia are viable and continue to grow slowly with dense branching, but do not conidiate. They quickly resume normal growth when shifted to a permissive temperature (692, 1068). Recessive in duplications (808); apparent dominance in heterokaryons (374) may have resulted from a shift in nuclear ratios. Used in studies of septation and branching (202), growth-inhibiting mucopolysaccharide (878, 879), and sulfate transport (641). Cell wall analysis (374). Growth is stimulated by lysine or arginine (0.1 mM) on glucose media at high temperatures (615). Because of high viability and tightly restricted growth at restrictive temperatures and normality at 25°C, cot-1 mutants have valuable technical applications. For example, crosses homozygous for cot-1 have been used in combination with sorbose for experiments with rec genes, where high-density ascospore platings are required for precise quantitative analysis of intralocus recombination (e.g., references 165, 997, and 1070). In another application, when shifted up after initial growth at the permissive low temperature, cot-1hyphae assume a "bottle brush" appearance with small side branches (692). This has been used to select uvs mutants by subsurface survival on UV-irradiated plates containing p-aminobenzoic acid (938; D.E.A. Catcheside, personal communication). cot-1 conidia or ascospores from cot-1 x cot-1crosses are used for replication in a protocol involving transfer by filter paper (615). For suppressors of cot-1, see gul.	IVR	B
his-3	IR. Right of met-10 (R.L. Metzenberg, personal communication). Left of cog (1 to 3%) (172,174), ure-4 (1%) (78), and ad-3A (1%) (271). (434)Requires histidine (434). Complex gene coding for histidinol dehydrogenase, phosphoribosyladenosine 5'-triphosphate-pyrophosphohydrolase, and phosphoribosyl-adenosine 5'-monophosphate-cyclohydrolase (16, 673) (Fig. 14). All three activities appear to be catalyzed by a single protein (673). Strains carrying different individual alleles may lack only the early reaction(s) or only histidinol dehydrogenase, or both. Those that lack only histidinol dehydrogenase accumulate histidinol (16, 162, 1123). Mutants produce cross-reacting material (220). Used to study intralocus complementation and recombination (15, 16, 27, 162, 164, 171, 172, 1121, 1122, 1124). Intralocus recombination is regulated by cog and by rec-2 (27, 171); it is not affected by rec-1 (172). Translocation T(IR;VII)TM429, with one breakpoint in his-3, has been used to show that cog is cis-acting (171). Initial alleles: C140 and T1710 (= C1710).	IR	B
nic-2	IR. Between ad-3B (4%) and ace-7 (4 to 7%) (271, 578). (482) Grows on nicotinic acid, nicotinamide, or high concentrations of quinolinic acid (97, 1168). Cannot use kynurenine, hydroxykynurenine, or hydroxyanthranilic acid (96, 1168). Accumulates 3-hydroxyanthranilic acid (96) (Fig. 18). Aging cultures accumulate red-brown pigment in the medium. Used to study intralocus recombination (908). Translocations T(4540) and T(S1325)are inseparable from nic-2 (808, 908, 911).	IR	B
pan-2	VIR. Right of rib-1 (<1 to 3%). Left of del (6%) and trp-2(11%) (140, 141, 143, 818, PB). Unable to convert ketovaline to ketopantoic acid (138, 140, 141). Used in major studies of intralocus recombination and complementation (140-143). pan-2ascospores remain white or pale if the crossing medium is not supplemented, even when the protoperithecial parent is pan-2+. Asci in which gene conversion has occurred at pan-2 can thus be recognized and isolated (1072, 1073); photographs (1072). For good recovery of pan-2progeny, crossing media should be supplemented with pantothenic acid (10 µg/ml) even when the protoperithecial parent is pan+. Called group B.	VIR	B
al-1	IR. Right of hom (<1%), arg-6 (<1 to 4%), T(T54M94), and al-2. Left of lys-3 (9%). (797, 808; D.D. Perkins, unpublished data). (482) Carotenoids abnormal. Strains carrying the various alleles differ widely in phenotype, ranging from white (e.g., 4637) and "aurescent" (pigment in peripheral conidia and conidiophores, 34508) to yellow mycelia and conidia (e.g., ALS4 and RES-25). See, for example, reference 1042. Strains carrying alleles ALS-14, RES-6, 34508, and RES-25 contain large amounts of phytoene (99 to 100% of the total neutral carotenoids), suggesting a lesion that affects phytoene dehydrogenase (398, 1039) (see Fig. 9). Strains carrying allele RWT-ylo accumulate zeta carotene and smaller amounts of neurosporene, suggesting a leaky block of the step between these intermediates (1071). It is not known whether phytoene dehydrogenase catalyzes the whole series of dehydrogenations or whether leakiness of this enzyme accounts for the different mutant phenotypes. For complementation tests, see references 500, 1039, and 1041. Fine-structure mapping (500, 1042). Translocation T(4637), inseparable from al-1, was the first albino mutation and one of the first chromosome rearrangements in Neurospora to be identified and studied (656). Allele 34508 called aur: aurescent.	IR	B