Abstract Detail

Genetics/Molecular Biology

Branco, Sara [1], Taylor, John W. [1], Bruns, Thomas D. [1].

Recent divergence in fungal populations.

Genetic differentiation between populations, signaling the effects of reduced gene flow and adaptation that are the main drivers of speciation, is essential to understanding biodiversity. Very little is currently known about how fungal populations differentiate in nature. Here, we investigate the divergence of a coastal and a mountain population of Suillus brevipes, a widespread mycorrhizal fungus associated with pine forests. Whole genome assembly and resequencing of 28 S. brevipes individuals revealed 567,192 shared SNPs that supported two recently diverged populations, each with low genetic diversity. As expected, mean genome-wide Fst is very low, indicating little overall population differentiation. However, genome-wide scans for regions of high differentiation using 5kb windows, reveal several highly differentiated regions, that harbor eight genes coding for five known proteins associated with cellular processes and signaling. Demographic inference suggests the two populations are isolated, with no migration between the coast and mountain. Population genetic differentiation and adaptation can occur by natural selection or genetic drift. Tests of the ratio of non-synonymous to synonymous mutations and identity of genes in the highly diverged regions may provide evidence of natural selection and suggest modes of adaptation. Further research including other mountain and coastal S. brevipes populations will be needed to identify the sources of the highly diverged regions.

1 - University of California, Plant and Microbial Biology, 321 Koshland Hall, Berkeley, CA, 94720, USA

Keywords:
adaptation
Population genomics
Suillus brevipes.

Presentation Type: Offered Paper - Paper
Session: 3
Location: Room 104 AB/Kellogg Hotel and Conference Center
Date: Monday, June 9th, 2014
Time: 8:30 AM
Number: 3001
Abstract ID:36
Candidate for Awards:None