A Meiotic Uv-Sensitive Mutant That Causes Deletion of Duplications in Neurospora
AUTOR(ES)
Newmeyer, Dorothy
RESUMO
The meiotic-3 (mei-3) mutant of Neurospora crassa has several effects: (1) When homozygous, it almost completely blocks meiosis and ascospore formation, (2) it is sensitive to UV, (3) its growth is inhibited by histidine and, (4) it increases the instability of nontandem duplications. This was shown for duplications produced by five different rearrangements and was demonstrated by two different criteria. The effects on meiosis and duplication instability are expressed strongly at 25°; the effects on sensitivity to UV and to histidine are expressed strongly at 38.5° but only slightly at 25°. Nevertheless, all four effects were shown to be due to a single gene. mei-3 is not allelic with previously reported UV-sensitive mutants.—Two other results were obtained that are not necessarily due to mei-3: (1) A cross involving mei-3 produced a new unlinked meiotic mutant, mei-4, which is not sensitive to UV or histidine, and (2) a burst of several new mutants occurred in a different mei-3 stock, including a partial revertant of mei-3.—mei-3 has previously been shown to cause frequent complete loss of a terminal duplicate segment, beginning exactly at the original rearrangement breakpoint. Possible mechanisms are discussed by which a UV-sensitive mutant could cause such precise deletions.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1213836Documentos Relacionados
- Postincision steps of photoproduct removal in a mutant of Bacillus cereus 569 that produces UV-sensitive spores.
- Isolation and characterization of a UV-sensitive mutator (mutB1) mutant of Haemophilus influenzae.
- Isolation of recombination-defective and UV-sensitive mutants of Bacillus megaterium.
- Rodent UV-sensitive mutant cell lines in complementation groups 6-10 have normal general excision repair activity.
- Characterization of Lactococcus lactis UV-sensitive mutants obtained by ISS1 transposition.