Nine mutagen sensitive (mus) mutants of Aspergillus nidulans were analyzed for effects on recombination. These mus show increased sensitivity to various mutagens; several were UV-sensitive. The majority were sterile in homozygous crosses homozygous mus diploids were essential to test for mitotic recombination. / Two distinct tests were used: intergenic recombination between colour mutations and their centromeres; and, intragenic recombination between two distinguishable adE alleles. Both hyper- and hypo-rec mus mutations were identified, with 15- to 20-fold differences between them. Three mutations musN, musO, and musQ had greatly elevated recombination frequencies. Only one, musL significantly reduced recombination but consequently increased malsegregation. / Analysis of the genotype of ad$ sp{+}$ recombinants, from musN and musL diploids, revealed qualitative differences from mus$ sp{+}$. musN enhanced mitotic crossing over but not gene conversion; while musL reduced the frequency of simple convertants but increased that of complex homozygous ad$ sp{+}$ genotypes. Mitotic conversion and crossing over, generally associated with each other, were uniquely affected in such mus diploids.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.60456 |
| Date | January 1990 |
| Creators | Zhao, Ping, 1955- |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Biology.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001235602, proquestno: AAIMM67631, Theses scanned by UMI/ProQuest. |
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