Academic Journal

Dicyemida and Orthonectida: Two Stories of Body Plan Simplification

التفاصيل البيبلوغرافية
العنوان: Dicyemida and Orthonectida: Two Stories of Body Plan Simplification
المؤلفون: Oleg A. Zverkov, Kirill V. Mikhailov, Sergey V. Isaev, Leonid Y. Rusin, Olga V. Popova, Maria D. Logacheva, Alexey A. Penin, Leonid L. Moroz, Yuri V. Panchin, Vassily A. Lyubetsky, Vladimir V. Aleoshin
المصدر: Frontiers in Genetics, Vol 10 (2019)
بيانات النشر: Frontiers Media S.A., 2019.
سنة النشر: 2019
المجموعة: LCC:Genetics
مصطلحات موضوعية: Mesozoa, Dicyemida, Orthonectida, genome, mitochondrial DNA, phylogeny, Genetics, QH426-470
الوصف: Two enigmatic groups of morphologically simple parasites of invertebrates, the Dicyemida (syn. Rhombozoa) and the Orthonectida, since the 19th century have been usually considered as two classes of the phylum Mesozoa. Early molecular evidence suggested their relationship within the Spiralia (=Lophotrochozoa), however, high rates of dicyemid and orthonectid sequence evolution led to contradicting phylogeny reconstructions. Genomic data for orthonectids revealed that they are highly simplified spiralians and possess a reduced set of genes involved in metazoan development and body patterning. Acquiring genomic data for dicyemids, however, remains a challenge due to complex genome rearrangements including chromatin diminution and generation of extrachromosomal circular DNAs, which are reported to occur during the development of somatic cells. We performed genomic sequencing of one species of Dicyema, and obtained transcriptomic data for two Dicyema spp. Homeodomain (homeobox) transcription factors, G-protein-coupled receptors, and many other protein families have undergone a massive reduction in dicyemids compared to other animals. There is also apparent reduction of the bilaterian gene complements encoding components of the neuromuscular systems. We constructed and analyzed a large dataset of predicted orthologous proteins from three species of Dicyema and a set of spiralian animals including the newly sequenced genome of the orthonectid Intoshia linei. Bayesian analyses recovered the orthonectid lineage within the Annelida. In contrast, dicyemids form a separate clade with weak affinity to the Rouphozoa (Platyhelminthes plus Gastrotricha) or (Entoprocta plus Cycliophora) suggesting that the historically proposed Mesozoa is a polyphyletic taxon. Thus, dramatic simplification of body plans in dicyemids and orthonectids, as well as their intricate life cycles that combine metagenesis and heterogony, evolved independently in these two lineages.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1664-8021
Relation: https://www.frontiersin.org/article/10.3389/fgene.2019.00443/full; https://doaj.org/toc/1664-8021
DOI: 10.3389/fgene.2019.00443
URL الوصول: https://doaj.org/article/a46a5611fb514da1a965d6a21c14a703
رقم الانضمام: edsdoj.46a5611fb514da1a965d6a21c14a703
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:16648021
DOI:10.3389/fgene.2019.00443