Karolina Susek, Wojciech K. Bielski, Robert Hasterok, Barbara Naganowska, Bogdan Wolko
Abstract
Insight into plant genomes at the cytomolecular level provides useful information about their karyotype structure, enabling inferences about taxonomic relationships and evolutionary origins. The Old World lupins (OWL) demonstrate a high level of genomic diversification involving variation in chromosome numbers (2n = 32-52), basic chromosome numbers (x = 5-7, 9, 13) and in nuclear genome size (2C DNA = 0.97-2.68 pg). Lupins comprise both crop and wild species and provide an intriguing system to study karyotype evolution. In order to investigate lupin chromosome structure, heterologous FISH was used. Sixteen BACs that had been generated as chromosome markers for the reference species, Lupinus angustifolius, were used to identify chromosomes in the wild species and explore karyotype variation. While all "single-locus" in L. angustifolius, in the wild lupins these clones proved to be "single-locus," "single-locus" with additional signals, "repetitive" or had no detectable BAC-FISH signal. The diverse distribution of the clones in the targeted genomes suggests a complex evolution history, which possibly involved multiple chromosomal changes such as fusions/fissions and repetitive sequence amplification. Twelve BACs were sequenced and we found numerous transposable elements including DNA transposons as well as LTR and non-LTR retrotransposons with varying quantity and composition among the different lupin species. However, at this preliminary stage, no correlation was observed between the pattern of BAC-FISH signals and the repeat content in particular BACs. Here, we describe the first BAC-based chromosome-specific markers for the wild species: L. cosentinii, L. cryptanthus, L. pilosus, L. micranthus and one New World lupin, L. multiflorus. These BACs could constitute the basis for an assignment of the chromosomal and genetic maps of other lupins, e.g., L. albus and L. luteus. Moreover, we identified karyotype variation that helps illustrate the relationships between the lupins and the extensive cytological diversity within this group. In this study we premise that lupin genomes underwent at least two rounds of fusion and fission events resulting in the reduction in chromosome number from 2n = 52 through 2n = 40 to 2n = 32, followed by chromosome number increment to 2n = 42.
This research output has an Altmetric Attention Score of 1. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 24 April 2018.
All research outputs
#15,380,722
of 22,881,964 outputs
Outputs from Frontiers in Plant Science
#10,899
of 20,270 outputs
Outputs of similar age
#236,572
of 365,664 outputs
Outputs of similar age from Frontiers in Plant Science
#240
of 498 outputs
Altmetric has tracked 22,881,964 research outputs across all sources so far. This one is in the 22nd percentile – i.e., 22% of other outputs scored the same or lower than it.
So far Altmetric has tracked 20,270 research outputs from this source. They receive a mean Attention Score of 4.0. This one is in the 40th percentile – i.e., 40% of its peers scored the same or lower than it.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 365,664 tracked outputs that were published within six weeks on either side of this one in any source. This one is in the 26th percentile – i.e., 26% of its contemporaries scored the same or lower than it.
We're also able to compare this research output to 498 others from the same source and published within six weeks on either side of this one. This one is in the 45th percentile – i.e., 45% of its contemporaries scored the same or lower than it.
