Taxonomic distribution of proteins containing SMI1_KNR4 domains

The tree below includes only several representative species and genera. The complete taxonomic breakdown of all proteins containing SMI1_KNR4 domains can be accessed here. Click the counts or percentage values to display the corresponding proteins.

Cloning and characterization of a Neurospora crassa gene required for(1,3) beta-glucan synthase activity and cell wall formation.

Enderlin CS, Selitrennikoff CP
Proc Natl Acad Sci U S A. 1994; 91: 9500-4

The glucan synthase 1 gene (gs-1) is required for (1,3) beta-glucansynthase activity [E.C. 2.4.1.34; UDP glucose:1,3-beta-D-glucan3-beta-D-glucosyltransferase] and for cell wall formation. The gs-1 genewas cloned by functional complementation of the cell-wall-less defect ofthe (1,3) beta-glucan synthase-deficient mutant, TM1, by using a genomicNeurospora crassa cosmid library. A 2568-nucleotide gs-1 cDNA sequencerevealed a 532-amino acid open reading frame encoding a polypeptide of 59kDa. The predicted gs-1 gene product has no obvious signal peptidecleavage sites or transmembrane domains. A gs-1 null mutant is defectivefor cell wall formation and (1,3) beta-glucan synthase activity. Thepredicted GS-1 protein is weakly homologous to a putative Saccharomycescerevisiae transcriptional regulatory protein.

Cloning and characterization of KNR4, a yeast gene involved in(1,3)-beta-glucan synthesis.

Hong Z, Mann P, Brown NH, Tran LE, Shaw KJ, Hare RS, DiDomenico B
Mol Cell Biol. 1994; 14: 1017-25

k9 killer toxin from Hansenula mrakii was used to select a number ofresistant mutants from Saccharomyces cerevisiae. Preliminary biochemicaland genetic studies showed that some of them acquired structural defectsin the cell wall. One of these mutants, the knr4-1 mutant, displays anumber of cell wall defects, including osmotic sensitivity; sensitivity tocercosporamide, a known antifungal agent; and resistance to Zymolyase, a(1,3)-beta-glucanase. We report here the isolation and analysis of theKNR4 gene. DNA sequence analysis revealed an uninterrupted open readingframe which contains five potential start codons. The longest codingtemplate encodes a protein of 505 amino acids with a calculated molecularmass of 57,044 Da. A data base search revealed 100% identity with anuclear protein, SMI1p. Disruption of the KNR4 locus does not result incell death; however, it leads to reduced levels of both (1,3)-beta-glucansynthase activity and (1,3)-beta-glucan content in the cell wall. The genewas mapped to the right arm of chromosome VII.