FGSC #5552

Mutant Type

Genus: N

reporting_genes: arg-3 ad-3A ad-3B nic-2 al-1;ad-2;inl

species: Neurospora crassa

allele: 30300 1-112-13 35203 43002 1-234-471;1-175-256;JH319

stock: 74-OR85-24a

glasgow:

mutagen:

Depositor: FJD

Link Group: IR R R R R;IIIR;VR

MT: a

Species No: 10

gene_back: SL

oppmt: 5554

trans:

ref1:

ref2:

site:

country:

ksudc_link: https://digital.lib.k-state.edu/item/neurospora-crassa/fgsc-5552

ksudc_link_html: https://digital.lib.k-state.edu/item/neurospora-crassa/fgsc-5552 ↗

Genes

Locus	Cultural Requirements	Link Group	Type
ad-2	IIIR. Between thi-2 (1%) and trp-1 (1 to 7%) (11, 219). (482) Requires adenine or hypoxanthine (682). Controls conversion of phosphoribosylformylglycineamidine to AIR (120) (Fig. 8). Strains carrying allele 70004(t) are heat sensitive (34°C versus 25 C) (682) and osmotic remediable (636). Called complementation group H.	IIIR	B
ad-3A	IR. Between his-3 (1 to 2%) and ad-3B (0.1 to 0.7%) (271). Right of ure-4 (78). (482) Requires adenine or hypoxanthine (682). Blocked in interconversion of CAIR plus aspartate to SAICAR (348) (Fig. 8). Produces purple pigment, permitting direct visual selection (276, 682); see the ad-3B entry. Reduced interallelic fertility (407). No interallelic complementation (267; F.J. de Serres, personal communication). ad-3A and ad-3B are two genetically and functionally distinct loci separated by a short but functionally complex region of unknown but essential function (271, 407). They have been used intensively for quantitative genetic and molecular studies of mutation (for a review, see reference 35). Either forward mutation (e.g., reference 277) or reverse mutation (e.g., reference 772) can be measured precisely; the former is detected visually by purple pigment. Purple pigment has also been used to assess the effect of histidine and tryptophan on purine nucleotide synthesis (786). Alleles N23 and N24 have been used as mutagen testers. N23 reverts with agents that cause base pair substitutions; N24 reverts with agents that cause frameshifts (772). SK(ad-3A) is at or near ad-3A and may be a cryptic ad-3A allele. Does not require adenine. In SK(ad-3A)x ad-3Acrosses, the ad-3A progeny die; possibly SK(ad-3A) mutants fail to make enough adenine to support their growth (251). Translocations Y155M64 ad-3A (272; PB) and Y112M15 ad-3A(413) each have one breakpoint that is inseparable from ad-3A. Called complementation group A (264). "A" in the locus symbol does not refer to mating type.	IR	B
ad-3B	IR. Between ad-3A (0.1 to 0.7%) and nic-2 (3%) (271). (482) Uses adenine or hypoxanthine (682). Blocked in interconversion of AIR to CAIR (348) (Fig. 8). Produces purple pigment, permitting direct visual selection (276, 682). Pigment is secreted with low concentrations of adenine (e.g., 0.1 mM), not with high concentrations (2 mM) (276, 682, 785). Pigment production used to assess effect of histidine and tryptophan on purine nucleotide synthesis (786). Reduced interallelic fertility (264, 407). Complementation maps (268, 274). Relation of mutagens to complementation patterns (269). Mutants with non-polarized complementation patterns on the right side of the complementation map grow on minimal medium if supplied with CO2; other mutants do not respond to CO2, (270). Used extensively for mutagenesis (see ad-3A). Rearrangement T(I- >III)Y112M4i ad-3B, which has a breakpoint inseparable from ad-3B, was the first insertional translocation to be reported for fungi (266). Allele 7-017-0137 shows "fixed instability," mutating to an unstable prototrophic allele (41). Alleles 2-17-126, 12-21-28, and numerous others are supersuppressible (408, 749, 955). Called complementation group B.	IR	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
arg-3	Uses citrulline or arginine.	IL	B
inl	VR. Between pho-3 (3 to 4%) and pab-1 (1 to 10%). Right of al-3 (362, 397, 1036). (482)Requires inositol (65). Lacks D-myoinositol-1-phosphatase (1142). Lack of glucocycloaldolase found by Pina and Tatum (826) is attributed by Williams (1142) to drastic repression of glucocycloaldolase by the concentration of inositol used for growth. Growth is colonial on low levels of inositol (367). Tends to extrude dark pigment into the medium when grown on suboptimal inositol. Composition of phospholipids and cell walls is abnormal on limiting inositol (367, 439, 440, 501). Inhibited by hexachlorocyclohexane (366, 457, 931). Conidia are subject to death by unbalanced growth on minimal medium (1028, 1033), a property exploited for mutant enrichment ("inositol-less death") (606, 647) because double mutants are at a selective advantage. Heat-sensitive allele 83201 is especially useful for mutant enrichment (832, 1043). Used in the first experiments reporting transformation of Neurospora by N. crassaDNA (677, 679) and reported to be efficient as a recipient in absence of inositol (1162). Used to study glucose (917) and sulfate (641) transport systems. Used extensively for studying induced reversion (392). Used for studying the mechanism of inositol-less death (647, 702), mutagenicity of ferrous ions, and regulation of mitochondrial membrane fluidity; for a review, see reference 702. Spontaneous reversion rates (386). Allele-specific partial suppressor (390). Allele 46802 is nonrevertable and inseparable from translocation 46802 (386, 808). Strains carrying heat-sensitive allele 83201 show slow semicolonial growth in liquid minimal medium at 25°C (641), but look normal on slants (D.D. Perkins, unpublished data). Strains carrying allele 89601 contain cross-reacting material (1183). Mutant gene exo-1 is present in the inl(89601) a stock FGSC 498 and may, therefore, be present in stocks of mutants derived by inositol-less death. (See references 194, 325, and 1027). Called inos.	VR	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