FGSC #5602

Mutant Type

Genus: N

reporting_genes: his-3 al-1;ad-2;mtr col-4 cot-1

species: Neurospora crassa

allele: 1-152-111 1-234-471;1-175-256;17-1-64 70007 C102(t

stock: 74-OR226-236

glasgow:

mutagen:

Depositor: FJD

Link Group: IR R;IIIR;IVR R R

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-5602

ksudc_link_html: https://digital.lib.k-state.edu/item/neurospora-crassa/fgsc-5602 ↗

Genes

Locus	Cultural Requirements	Link Group	Type
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
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 (797, 808; D.D. Perkins, unpublished data).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
mtr	IVR. Between pdx-1 (2%) and col-4 (1%) (101, 1017).Resistant to 4-methyltryptophan and p-fluorophenylalanine. pmn (= Pm-N, pm n), selected by resistance to p-fluorophenylalanine, has been shown to be alletic with mtr(R. Sadler and S. Ogilvie-Villa, personal communication; see also reference 248). Defective in transport of neutral aliphatic and aromatic amino acids via amino acid transport system I (as defined in reference 777) (248, 602, 1017, 1152). Causes an alteration in surface glycoproteins (1038). Used extensively for transport studies (247a, 1150 [review], 1152), also for studies of the mechanism of intralocus recombination (1021). Resistance is recessive in duplications from T(S1229) (PB). Recessive resistance used in a heterokaryon test system for mutation studies (1020). Suppressors obtained and used for selecting other resistance mutants (106, 107, 555, 1018). Allele 26 is a putative frameshift mutation reverted by ICR170 (106, 107). mtrascospores are slow to darken and mature; up to 50% of the young ascospores from heterozygous crosses are white (152, PB). With probable allele MN18, ascospore viability is improved by the addition of peptone to the crossing medium when the male parent is added (152). mtr has been scored on media containing 10 or 70 µg of filter-sterilized 4-methyltryptophan per ml or on 20 or 60 µg of p-fluorophenylalanine per ml (550, 1021, PB). Unlike 4-methyltryptophan, p-fluorophenylalanine is heat stable and can be added before autoclaving. Strains with mutations at the mtr locus may be obtained by selection for resistance to numerous agents or for defects in uptake ability. Thus, there is confusion in nomenclature. Genes originally designated neua, neur, neut, tru(628) may be mtr alleles. mtr was initially called mt (602).	IVR	B
col-4	IVR. Between met-1 (4%) and arg-2 (<1 to 2%) (692, 876, 991). (695) Spreading colonial morphology, forming dense balls of conidia high in slants (47). Probably dominant in heterozygous duplications from T(S1229) (E.G. Barry, personal communication). Cell wall-autolyzing enzyme (631). Reduced amount of cell wall peptides (1165). Used in combination with pe fl to produce microconidiating colonial growth suitable for reversion experiments (386). Called spco-1 (382); called c (386).	IVR	B
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
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