kex-1 : kex-like-1
Changed to scp.
kin-1 : kinesin-1
Unmapped.
Cloned and sequenced: Swissprot KINH_NEUCR, EMBL/GenBank L47106, EMBL NCNKIN, GenBank NEUKIN.
Specifies a plus-end-directed motor molecule functionally homologous to the kinesin heavy chain of animals. The motor domain at the amino-terminal end shows homology with those of conventional kinesins, and there is a short region of homology near the C-terminus (1999). The central stalk domain is unique in sequence, however. A null mutant obtained by RIP shows severely altered morphology and branching, reduced linear growth, abnormal nuclear distribution in mycelia, and increased nuclear number in conidia. Motility of organelles, examined using video microscopy, is unaffected. The Spitzenkörper is difficult to detect. The defect is thought to be in the transport of secretory vesicles to sites of cell-wall biosynthesis (1870). Apical movement of vesicular organelles to the Spitzenkörper is defective, and protein secretion into the medium is deficient. Used to examine the kinesin-dynein (kin; ro-1) double mutant, which is defective in oppositely directed microtubule motors, and to compare it with the single mutants (1871). Used to examine the role of the motor domain in determining the direction of movement in molecular chimeras of the Neurospora kinesin with an oppositely oriented kinesin homolog, NCD (nonclaret disjunctional dominant in Drosophila) (870). Growth rate of the null mutant was used to assay the functional efficiency of mutant kinesins from various sources (1068). For a review of fungal molecular motors, see ref. (2258).
krev-1 : Krev-1-like
IL. Linked to nit-2, mus-18 (0/18) (969, 970, 1447). A report of linkage to ser-1 and pro-1 in IIIR apparently was in error (1446).
Cloned and sequenced: EMBL/GenBank AB000281.
Homolog of mammalian Krev-1, a member of the RAS superfamily. Null mutants obtained by RIP are fertile and vegetatively normal. Overexpression of krev mutants inhibits perithecial development (969).
kyn-1 : kynureninase
VII. Linked to nic-3 (30%), wc-1 (20%) (1180).
Partially defective in the induction of the inducible kynureninase I (EC 3.7.1.3) isozyme by kynurenine, indole, or tryptophan but has normal levels of the constitutive kynureninase II isozyme. Possibly regulatory. Scored and selected by a low level of anthranilate accumulation on medium supplemented with a high level of tryptophan; this results in lowered UV fluorescence compared to wild type (1813). The inducible kynureninase is inactivated by incubation with L-alanine or L-ornithine. The inactivated enzyme is resolved to the apoenzyme by dialysis and reactivated by incubation with pyridoxamine 5'-phosphate plus pyruvate or with pyridoxal 5'-phosphate (2049).
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