Abstract Detail

Lightning Talks – Germinating Ideas

Stewart-Ahn, Heather [2], Balderas, Eli [1], Cady, Gwendelen [2], Fetters, Alexandra [2], Huff, Trevor [2], Johnson, Michelle [2], Pfeffer, Bubba [2], Roussa, Lucy [2], Allen, Jessica [2].

Draft genome sequences of two critically endangered lichens: Sticta deyana and Sulcaria isidiifera.

Characterizing the genome of endangered species is vital to documenting biodiversity, investigating population genetics, deciphering species distribution drivers, and shaping conservation objectives. In groups of organisms that are traditionally understudied and are particularly sensitive to anthropogenic change, such as lichens, whole genome sequencing may prove particularly important. Extremely sensitive to pollution as well as habitat loss, lichens are adept bioindicators used globally for monitoring air pollution, and they have been studied widely for their susceptibility to climate change incurred decline. To archive essential biodiversity data and to facilitate further lichen conservation genomics research, in this study we present high-throughput draft genomes of Sticta deyana Lendemer and Goffinet and Sulcaria isidiifera Brodo. Both species are categorized as critically endangered by the International Union for Conservation of Nature (IUCN). A photomorphic species endemic to eastern North America, populations of S. deyana are estimated at a total of 95 individuals. It predominantly occurs in coastal North Carolina, amid swamps on the bark of hardwoods, exclusively within the Dare Regional Lichen Biodiversity Hotspot, a nexus of biodiversity and endemism under threat of sea-level rise. In addition, a disjunct population of roughly 15 individuals occurs in northwest Alabama on non-calcareous rock where it associates with remnant old-growth Tsuga canadensis, under threat from wooly adelgid. In contrast, S. isidiifera is endemic to western North America, its distribution restricted to four increasingly fragmented subpopulations, in an area comprising less than 8 km² in San Luis Obispo County, California. An associate of old-growth coastal chaparral scrub, where it occurs on the bark of trees and shrubs, estimates of S. isidiifera populations have diminished since its discovery in 1986, with development and wildfire as its most prominent threats. We assembled nearly complete, highly contiguous genomes for both species. While the genome of S. deyana is within the range of most lichens (43.44 Mb), S. isidiifera has a substantially larger genome (71.3 Mb). The gene content in both species was similar, and the large size of the S. isidiifera genome is due to a higher quantity of repetitive regions (6.6% for S. deyana and 21.6% for S. isidiifera). Moreover, there was also a great difference in biosynthetic gene clusters (BGCs)— antiSMASH identified 16 BGCs for S. deyana and 50 BGCs for S. isidiifera. Our data has been deposited on the European Nucleotide Database via the European Molecular Biology Laboratory and the European Bioinformatics Institute (EMBL-EBI) where it will be accessible to the public and available for further research applications that could lead to a better understanding of endemic speciation and lichen biodiversity.

1 - California Polytechnic State University, San Luis Obispo, 9315 Rivera Lane, APT A, Atascadero, CA, 93422, United States
2 - Eastern Washington University, Biology, 258 Science Building, Cheney, WA, 99004, USA

Keywords:
genomics
Biodiversity
conservation
endangered species
Endemic Species
lichens.

Presentation Type: Germinating Ideas Lightning Talk
Number: LT2001
Abstract ID:821
Candidate for Awards:A. J. Sharp Award