Phenotypic and epistatic grouping of hypo- and hyper-rec mus mutants in Aspergillus |
| |
Authors: | Etta Kafer Shun-Kee Chae |
| |
Institution: | (1) Department of Biology, McGill University, H3A 1B1 Montreal, Canada;(2) Present address: Institute of Molecular Biology and Biochemistry, Department of Biological Sciences, Simon Fraser University, V5A 1S6 Burnaby, B.C., Canada;(3) Present address: Department of Chemistry and Biochemistry, UCLA, 90024-1569 Los Angeles, CA, USA |
| |
Abstract: | The mutants musK to musS of Aspergillus nidulans are sensitive to methyl-methanesulfonate (MMS) and several of them are meiotic-defective and alter mitotic recombination frequencies. All were found to be cross-sensitive to 4-nitro-quinoline-N-oxide (4-NQO) but unexpectedly none of them was hypersensitive to -rays and few to UV light. Double mus;uvs mutants were constructed to test for interactions with uvs mutations of the four epistatic groups of Aspergillus, UvsF , UvsC , UvsI , and UvsB . All meiotic-defective mus mutations caused some lethal interactions, usually with uvsF. None of them showed epistasis with UvsF or UvsB group mutants and one, musO, may represent a new group. Three mus mutations that affect recombination were assigned to the UvsC group, namely musN and K, and also musL which is recombination-defective and closely resembles uvsC. While uvsC mutants are mutators and lack UV-mutagenesis, most mus mutants had no effects on mutation. Only musR, which appeared epistatic with uvsI, showed reduced UV-reversion frequencies similar to uvsI. The recombination-proficient mus mutants appeared to be epistatic with more than one group, but in several cases sensitivities were slight and overlaps insufficient to obtain corroborating results with MMS and 4-NQO. |
| |
Keywords: | DNA repair MMS sensitivity Epistatic groups Recombination genes Aspergillus nidulans |
本文献已被 SpringerLink 等数据库收录! |
|