Male Transmission of Linear Plasmids and Mitochondrial DNA in the Fungus Neurospora
AUTOR(ES)
Yang, X.
RESUMO
One of the general rules of heredity is that in anisogamous matings genetic elements in organelles are inherited maternally. Nevertheless, there are cases of paternal transmission, both as rare exceptions, and as regular modes of inheritance. We report two new cases of paternal transmission in crosses of the model fungus Neurospora. First, we show leakage of a linear plasmid from males, the first case in fungi and the second in eukaryotes. Transmission frequencies ranged from 1% to 15% in different crosses, but some crosses showed no detectable male transmission. Second, we show leakage of male mitochondrial DNA (mtDNA), the second case in fungi. Some of the resulting progeny have only the male mtDNA type, but some are heteroplasmons. Heteroplasmons show novel restriction fragments attributable to recombination or rearrangement. Heteroplasmy of mtDNA through male transmission has not been reported previously in any eukaryote. In addition we have shown paternal leakage of circular mitochondrial plasmids, supporting another reported case. In a male bearing a linear and a circular plasmid, these plasmids and the mtDNA are transmitted in different combinations. These results show a potential for mitochondrial segregation and assortment during the sexual cycle in anisogamous fungi, pointing to more potential avenues for novel associations between genomic compartments, and between genomic and extragenomic elements.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1205574Documentos Relacionados
- Inheritance of Mitochondrial DNA and Plasmids in the Ascomycetous Fungus, Epichloe Typhina
- Distribution and evolutionary significance of mitochondrial plasmids in Neurospora spp.
- Transmission of mitochondrial deoxyribonucleic acid in Neurospora crassa sexual crosses.
- Linear mitochondrial plasmids of Fusarium oxysporum contain genes with sequence similarity to genes encoding a reverse transcriptase from Neurospora spp.
- Two Neurospora mitochondrial plasmids encode DNA polymerases containing motifs characteristic of family B DNA polymerases but lack the sequence Asp-Thr-Asp.
