Abstract Detail

Bryology and Lichenology

Niu, Jingyuan [1], Zhang, Shijia [1], Zhang, Yijie [1], Shen, Fengjiao [2], Li, Lin [1], Shi, Shuo [2], Zhao, Jiancheng [1].

The Mitochondrial and Chloroplast Genomes Comparison and Evolution Analysis of Selected Taxa of Bryales (Musci).

Bryales is one of the ancient group of mosses with various species, which plays a vital role in the systematic evolution of bryophytes. The systemic research about mosses' genome level is still relatively lacking. The organelles' genome as a simpler genome (as opposed to the nuclear genome) becomes the multitudinous scholar's first choice. There are few studies on the evolution of the organelle genome of Bryales, especially the complete genome data of mitochondria and chloroplasts. The author systematically analyzed the basic features and the repetitive sequence and SSR sites of the mitochondrial genome and the prediction of RNA editing and codon bias and influence factors of the mitochondria and chloroplast genome of Bryales for the first time.     The following results were obtained: 1. The mitochondrial data of Bryales showed slow evolution and high conservation at the genomic level. 2. The number of RNA editing sites in the chloroplast genome was more than in the mitochondrial genome. 3. Organelles were affected by mutation pressure in codon usage, but selection pressure also played an essential role in the use of codon. 4. The phylogenetic tree of the selected taxa can well reflect the evolutionary relationship of the traditional genera of Bryaceae and Mniaceae and still cannot solve all the evolutionary relationships, such as the evolution problem of the subclassification of Pohlia. The fit relations between the morphological characters and molecular phylogenetic trees are not high. Many morphological characteristics were plesiomorphic, which could not reflect the real evolutionary relationships. 5. From the more fine geological time, the origin of time is around 50.55 Ma from the mitochondrial data and 37 Ma from the chloroplast data. The two organelles estimate large scales of geological time is relatively consistent, and all is in the Eocene (33.9-56.0 Ma). The study of comparative analysis and the evolutionary relationship of chloroplasts and mitochondria genome of the selected taxa of Bryales, combining the fossil record, morphological characters. Which filled the blank of Bryales genome level systemic research for the first time and enhanced the research of the moss organelles genome, and lay the foundation for the further study on nuclear genome level. The results also provide referable data and ideas for the weight of morphological traits and molecular data in the systematic classification of mosses and the study on the evolution process of mosses' genetic system.

1 - Hebei Normal University, College of Life Sciences, No.20, East Nanerhuan Road, Shijiazhuang, Hebei, 050024, China
2 - Hebei Normal University, College of Life Sciences, No. 20 East Nanerhuan Road, Shijiazhuang, Hebei, 050024, China

Divergence time

Presentation Type: Poster
Session: P, Bryology and Lichenology Posters
Location: Virtual/Virtual
Date: Monday, July 27th, 2020
Time: 5:00 PM Time and date to be determined
Number: PBL001
Abstract ID:654
Candidate for Awards:None

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