FGSC #6018

Mutant Type

Genus: N

reporting_genes: acr-2 trp-1 nit-7 dow

species: Neurospora crassa

allele: KH5 10575 V1M59 P616

stock: 3209

glasgow:

mutagen:

Depositor: DDP

Link Group: IIIL R 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-6018

ksudc_link_html: https://digital.lib.k-state.edu/item/neurospora-crassa/fgsc-6018 ↗

Genes

Locus	Cultural Requirements	Link Group	Type
nit-7	IIIR. Between trp-1 (26 to 32%) and dow (45%) (D.D. Perkins, unpublished data). Cannot use nitrate or hypoxanthine as a nitrogen source. Resembles nit-1, nit-8, and nit-9 in affecting the molybdenum-containing cofactor common to nitrate reductase and xanthine dehydrogenase (1080, 1081) (Fig. 19 and 24).	IIIR	B
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
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
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