RESUMO
Although cells of mushroom-producing fungi typically contain paired haploid nuclei (n + n), most Armillaria gallica vegetative cells are uninucleate. As vegetative nuclei are produced by fusions of paired haploid nuclei, they are thought to be diploid (2n). Here we report finding haploid vegetative nuclei in A. gallica at multiple sites in southeastern Massachusetts, USA. Sequencing multiple clones of a single-copy gene isolated from single hyphal filaments revealed nuclear heterogeneity both among and within hyphae. Cytoplasmic bridges connected hyphae in field-collected and cultured samples, and we propose nuclear migration through bridges maintains this nuclear heterogeneity. Growth studies demonstrate among- and within-hypha phenotypic variation for growth in response to gallic acid, a plant-produced antifungal compound. The existence of both genetic and phenotypic variation within vegetative hyphae suggests that fungal individuals have the potential to evolve within a single generation in response to environmental variation over time and space.
Assuntos
Armillaria/genética , Evolução Biológica , Hifas/genética , Esporos Fúngicos/genética , Núcleo Celular/genética , Citoplasma/genética , DiploideRESUMO
Methylobacterium sp. strain ARG-1 was isolated from a cell culture of hyphal tips of the white-rot fungus Armillaria gallica We describe here the sequencing, assembly, and annotation of its genome, confirming the presence of genes involved in methylotrophy. This is the first genome announcement of a strain of Methylobacterium associated with A. gallica.