Abstract Detail

Systematics

Davis, Jerrold I [1], Lim, Gwynne S [2], Barrett, Craig [3], Grace, Olwen [4], Conran, John G [5].

Rearrangements in the plastid genome of Ecdeiocolea monostachya (Ecdeiocoleaceae; Poales): multiple inversions, duplications, and modifications to the Inverted Repeat region.

The southwestern Australian endemic family Ecdeiocoleaceae comprises two genera and three species of caespitose, leafless, rush-like monocots that grow in sandy, nutrient-poor, dry heathlands. Ecdeiocoleaceae and the monogeneric family Joinvilleaceae are the two closest relatives of the grass family (Poaceae), and these three families share two inversions in the plastid genome. M.R. Duvall and W.P. Wysocki (2014; Botany2014 abstracts) reported two additional inversions in Joinvillea ascendens Gaudich. We have sequenced the plastome of Ecdeiocolea monostachya F. Muell., using Illumina paired-end short-read data, supplemented by targeted PCR amplifications to confirm putative rearrangements. We confirm the presence of the two inversions previously inferred for all three families, and report several additional novel rearrangements unique to E. monstachya. The inverted repeat (IR) regions of E. monostachya are substantially reduced in length, relative to those of the other two families, at the ends that are adjacent to the large single-copy (LSC) region, and there is a corresponding increase in the length of the LSC region. The gene arrangement within the remaining portions of the IR regions, and in the small single-copy (SSC) region, are largely co-linear with those of Joinvilleaceae and Poaceae, except that clpP lies within the IR regions, adjacent to rrn16. There are several additional rearrangements within the LSC region, which are interpretable as the results of additional inversions, and there are several small identical and nearly identical regions at the junctions between the rearranged gene blocks. Of the two inversions previously reported for Joinvillea, the larger may be shared with Ecdeiocolea, as two of the inversion junctions in Ecdeiocolea correspond to the endpoints of this inversion in Joinvillea; however, the smaller of the two inversions in Joinvillea appears to be lacking in Ecdeiocolea.

1 - Cornell University, Plant Biology and L.H. Bailey Hortorium, 412 Mann Library, Ithaca, NY, 14853, USA
2 - Cornell University (and New York Botanical Garden), Plant Biology and L.H. Bailey Hortorium, 412 Mann Library, Ithaca, NY, 14853, USA
3 - West Virginia University, Biology, Life Sciences Building, PO Box 6057, Morgantown, WV, 26506, USA
4 - Royal Botanic Gardens, Kew, Comparative Plant and Fungal Biology, Richmond, Surrey, TW9 3AB, UK
5 - University of Adelaide, ACEBB & SGC, Department of Genetics & Evolution, Benham Building DX 650 312, North Terrace, SA 5005, Australia

Keywords:
Ecdeiocolea
Poales
Monocotyledon
Plastome
inversion.

Presentation Type: Oral Paper
Session: 45, Monocots part B/Basal Eudicots
Location: 200/Savannah International Trade and Convention Center
Date: Wednesday, August 3rd, 2016
Time: 4:30 PM
Number: 45012
Abstract ID:771
Candidate for Awards:None