Abstract Detail

Comparative Genomics/Transcriptomics

Heyduk, Karolina [1], Jenkins, Jerry [2], Shu, Shengqiang [3], Field, Richard [4], MacNeill, Bryan [5], McKain, Michael [6], Barry, Kerrie [3], Schmutz, Jeremy [2], Leebens-Mack, Jim [7].

Insights into ancient polyploidy and photosynthetic gene family evolution from newly sequenced Yucca genomes.

The genus Yucca (Asparagaceae) consists of 51 accepted species, and has been a model system for research on pollinator mutualism coevolution and for studying the evolution of Crassulacean acid metabolism (CAM). Additionally, Yucca - and the core of the Agavoideae - have a bimodal karyotype that consists of five large chromosomes and 25 much smaller chromosomes. The origin of the bimodal karyotype within Agavoideae coincides with a polyploidy event but little was understood about how gene content and repetitive elements were dispersed across the large and small chromosomes, and how genome architecture underpins traits of interest, including CAM photosynthesis. Here we use newly sequenced, whole-chromosome genome assemblies of Yucca aloifolia (CAM), Y. filamentosa (C3), and Y. jaegeriana (C3) to investigate the origins of the bimodal karyotype. Whereas it was previously hypothesized that the bimodal karyotype was a product of an ancient allopolyploidy event, our data instead suggests an ancient genome triplication. We further explore gene and repetitive element content across the genomes to understand whether transposable elements may have led to the increase in size in a subset of chromosomes. Finally, we assess the copy number and genomic context of genes important for CAM to better understand the evolution of this modified photosynthetic pathway in Yucca.

1 - University Of Hawai'i, School Of Life Sciences, 1800 East-West Road, Honolulu, HI, 96822, United States
2 - HudsonAlpha, 601 Genome Way Northwest, Huntsville, AL, 35806, USA
3 - Joint Genome Institute, 2800 Mitchell Dr. #100, Walnut Creek, CA, 94598, USA
4 - University Of Georgia, Plant Biology, 120 Carlton St, 2203, Athens, GA, 30602, United States
5 - University Of Alabama , Department Of Biology, Science And Engineering Complex, 1325 Hackberry Ln, Tuiscaloosa, AL, 35401, United States
6 - University of Alabama, Biological Sciences, 411 Mary Harmon Bryant Hall, Tuscaloosa, AL, 35487, USA
7 - University Of Georgia, Plant Biology, 2101 Miller Plant Sciences, Athens, GA, 30602, United States

Keywords:
karyotype
chromosome
Photosynthesis
Genome Duplication
Yucca
CAM.

Presentation Type: Oral Paper
Session: CGT1, Comparative Genomics/Transcriptomics I
Location: /
Date: Tuesday, July 20th, 2021
Time: 11:00 AM(EDT)
Number: CGT1005
Abstract ID:838
Candidate for Awards:None