Dataset Information

Evolutionary Comparisons of the Chloroplast Genome in Lauraceae and Insights into Loss Events in the Magnoliids.

ABSTRACT: Available plastomes of the Lauraceae show similar structure and varied size, but there has been no systematic comparison across the family. In order to understand the variation in plastome size and structure in the Lauraceae and related families of magnoliids, we here compare 47 plastomes, 15 newly sequenced, from 27 representative genera. We reveal that the two shortest plastomes are in the parasitic Lauraceae genus Cassytha, with lengths of 114,623 (C. filiformis) and 114,963?bp (C. capillaris), and that they have lost NADH dehydrogenase (ndh) genes in the large single-copy region and one entire copy of the inverted repeat (IR) region. The plastomes of the core Lauraceae group, with lengths from 150,749?bp (Nectandra angustifolia) to 152,739?bp (Actinodaphne trichocarpa), have lost trnI-CAU, rpl23, rpl2, a fragment of ycf2, and their intergenic regions in IRb region, whereas the plastomes of the basal Lauraceae group, with lengths from 157,577?bp (Eusideroxylon zwageri) to 158,530?bp (Beilschmiedia tungfangensis), have lost rpl2 in IRa region. The plastomes of Calycanthus (Calycanthaceae, Laurales) have lost rpl2 in IRb region, but the plastome of Caryodaphnopsis henryi (Lauraceae) remain intact, as do those of the nonLaurales magnoliid genera Piper, Liriodendron, and Magnolia. On the basis of our phylogenetic analysis and structural comparisons, different loss events occurred in different lineages of the Laurales, and fragment loss events in the IR regions have largely driven the contraction of the plastome in the Lauraceae. These results provide new insights into the evolution of the Lauraceae as well as the magnoliids as a whole.

SUBMITTER: Song Y

PROVIDER: S-EPMC5610729 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Evolutionary Comparisons of the Chloroplast Genome in Lauraceae and Insights into Loss Events in the Magnoliids.

Song Yu Y Yu Wen-Bin WB Tan Yunhong Y Liu Bing B Yao Xin X Jin Jianjun J Padmanaba Michael M Yang Jun-Bo JB Corlett Richard T RT

Genome biology and evolution 20170901 9

Available plastomes of the Lauraceae show similar structure and varied size, but there has been no systematic comparison across the family. In order to understand the variation in plastome size and structure in the Lauraceae and related families of magnoliids, we here compare 47 plastomes, 15 newly sequenced, from 27 representative genera. We reveal that the two shortest plastomes are in the parasitic Lauraceae genus Cassytha, with lengths of 114,623 (C. filiformis) and 114,963 bp (C. capillaris ...[more]

PMID: 28957463

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Dataset Information

Evolutionary Comparisons of the Chloroplast Genome in Lauraceae and Insights into Loss Events in the Magnoliids.

Publications

Evolutionary Comparisons of the Chloroplast Genome in Lauraceae and Insights into Loss Events in the Magnoliids.

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