FGSC #4117

Mutant Type

Genus: N

reporting_genes: acr-2 leu-1 trp-1 dow

species: Neurospora crassa

allele: KH5(r) 33757 10575 P616

stock: M1293 A

glasgow:

mutagen:

Depositor: EK

Link Group: IIIC IIIR IIIR IIIR

MT: A

Species No: 10

gene_back:

oppmt: 4118

trans:

ref1: Kafer 1982. Neurospora Newsl. 29:41-44, https://doi.org/10.4148/1941-4765.1645

ref2:

site:

country:

ksudc_link: https://digital.lib.k-state.edu/item/neurospora-crassa/fgsc-4117

ksudc_link_html: https://digital.lib.k-state.edu/item/neurospora-crassa/fgsc-4117 ↗

Genes

Locus	Cultural Requirements	Link Group	Type
trp-1	IIIR. Between ad-2 (1 to 7%) and ro-2 (2 to 12%) (11, 219, 812). Linked to fpr-3 (< 1%) (550). (504). Uses tryptophan or indole (1060); strains carrying some alleles can also use anthranilate; others cannot (4). trp-1+ and trp-2+ gene products together form an enzyme aggregate with three activities: anthranilate synthetase, phosphoribosyl-anthranilate isomerase, and indoleglycerol-phosphate synthetase (181, 260) (Fig. 11). trp-1 codes for the beta subunit of the aggregate (546); it specifies phosphoribosyl-anthranilate isomerase, indoleglycerol-phosphate synthetase, and collaboratively the glutamine amino transferase activity of anthranilate synthetase (29, 181, 502). Strains carrying different alleles differ in lacking one or more of the three activities, e.g., trp-1 (allele 15) lacks all three activities; trp-1 (20) lacks only phosphoribosyl- anthranilate isomerase, trp-1C (1) lacks only anthranilate synthetase, trp-1 (25) lacks both phosphoribosyl-anthranilate isomerase and indoleglycerol-phosphate synthetase, etc. (259). (To avoid confusion, note that in reference 259 and related papers, the same "allele number" may be used for a trp-2 mutation, a trp-1 mutation [non-anthranilate-utilizing], and a trp-1Cmutation [anthranilate utilizing]; mutations of the last class are listed by FGSC as trp-1 with the allele number prefixed by C.) Strains carrying different alleles differ in their ability to form aggregates (181, 259). Association between trp-1 and trp-2products is essential for glutamine-dependent anthranilate synthetase activity but not the other two activities (181). The trp-1 gene has been cloned (545, 925), sequenced (925), and reintroduced into Neurospora by transformation (925). It is only partially expressed in E. coli. Fine-structure maps (10, 259). Complementation maps (10, 163). Reviewed as example of gene fusion (218). Nonsense allele used to demonstrate restoration of normal enzyme aggregate by supersuppressors (183). Alleles that accumulate anthranilate are scorable by blue fluorescence under long-wave UV after 2 to 5 days of growth on minimal medium plus indole (10 µg /ml), 34°C (814, 816). Aging cultures may produce brown pigment; blue fluorescence disappears as pigment forms.	IIIR	B
acr-2	III. Linked to thi-4 (0/286). Left of sc (3 to 6%) and spg (1 to 11%) (498, 816). acr-2 has been shown left of the centromere on published maps but without direct evidence. acr-2and trp-1 (on IIIR) cosegregated at the second division in 1 of 13 asci (H.B. Howe, Jr., personal communication), which would favor a right arm location. Resistant to acriflavine (494, 495); also resistant to 3-amino-1,2,4-triazole (seven alleles tested) (494). Resistance is probably dominant (heterokaryon tests) (498). Not resistant to malachite green. An excellent stable marker, fully fertile, with unambiguous scoring. Sizable inocula should be used to avoid false-negative tests. Use acriflavine at 50 µg /ml in minimal agar medium (816) (higher concentrations may be used) and aminotriazole at 0.5 mg/ml; both added before autoclaving.	III	B
dow	IIIR. Right of ty-1 (21%) and un-17 (23%); linked to erg-3 (10%) and acu-7(0/72) (816).Soft, matty growth, conidiating and covering slants (816). An excellent marker: good viability, fertility, and scorability.	IIIR	B
leu-1	IIIR. Between ad-4 (1 to 5%) and his-7 (8%) (219, 578, 815, 1052). (868)Requires leucine (867, 868). Lacks beta-isopropylmalate dehydrogenase (426) (Fig. 15). Accumulates alpha-isopropylmalate and beta-isopropylmalate (427). Synthesis of the enzyme also requires the function of regulatory gene leu-3+ and the presence of alpha-isopropylmalate, which acts as inducer (427). Resistant to aminotriazole (D. D. Perkins, unpublished data). Female sterile (O. M. Mylyk, personal communication). Used to study reversion and competition in heterokaryons (901).	IIIR	B