Dataset Information

Platypus and echidna genomes reveal mammalian biology and evolution.

ABSTRACT: Egg-laying mammals (monotremes) are the only extant mammalian outgroup to therians (marsupial and eutherian animals) and provide key insights into mammalian evolution^1,2. Here we generate and analyse reference genomes of the platypus (Ornithorhynchus anatinus) and echidna (Tachyglossus aculeatus), which represent the only two extant monotreme lineages. The nearly complete platypus genome assembly has anchored almost the entire genome onto chromosomes, markedly improving the genome continuity and gene annotation. Together with our echidna sequence, the genomes of the two species allow us to detect the ancestral and lineage-specific genomic changes that shape both monotreme and mammalian evolution. We provide evidence that the monotreme sex chromosome complex originated from an ancestral chromosome ring configuration. The formation of such a unique chromosome complex may have been facilitated by the unusually extensive interactions between the multi-X and multi-Y chromosomes that are shared by the autosomal homologues in humans. Further comparative genomic analyses unravel marked differences between monotremes and therians in haptoglobin genes, lactation genes and chemosensory receptor genes for smell and taste that underlie the ecological adaptation of monotremes.

SUBMITTER: Zhou Y

PROVIDER: S-EPMC8081666 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Platypus and echidna genomes reveal mammalian biology and evolution.

Zhou Yang Y Shearwin-Whyatt Linda L Li Jing J Song Zhenzhen Z Hayakawa Takashi T Stevens David D Fenelon Jane C JC Peel Emma E Cheng Yuanyuan Y Pajpach Filip F Bradley Natasha N Suzuki Hikoyu H Nikaido Masato M Damas Joana J Daish Tasman T Perry Tahlia T Zhu Zexian Z Geng Yuncong Y Rhie Arang A Sims Ying Y Wood Jonathan J Haase Bettina B Mountcastle Jacquelyn J Fedrigo Olivier O Li Qiye Q Yang Huanming H Wang Jian J Johnston Stephen D SD Phillippy Adam M AM Howe Kerstin K Jarvis Erich D ED Ryder Oliver A OA Kaessmann Henrik H Donnelly Peter P Korlach Jonas J Lewin Harris A HA Graves Jennifer J Belov Katherine K Renfree Marilyn B MB Grutzner Frank F Zhou Qi Q Zhang Guojie G

Nature 20210106 7856

Egg-laying mammals (monotremes) are the only extant mammalian outgroup to therians (marsupial and eutherian animals) and provide key insights into mammalian evolution<sup>1,2</sup>. Here we generate and analyse reference genomes of the platypus (Ornithorhynchus anatinus) and echidna (Tachyglossus aculeatus), which represent the only two extant monotreme lineages. The nearly complete platypus genome assembly has anchored almost the entire genome onto chromosomes, markedly improving the genome con ...[more]

PMID: 33408411

Similar Datasets

Project description:The Myriapoda, composed of millipedes and centipedes, is a fascinating but poorly understood branch of life, including species with a highly unusual body plan and a range of unique adaptations to their environment. Here, we sequenced and assembled 2 chromosomal-level genomes of the millipedes Helicorthomorpha holstii (assembly size = 182 Mb; shortest scaffold/contig length needed to cover 50% of the genome [N50] = 18.11 Mb mainly on 8 pseudomolecules) and Trigoniulus corallinus (assembly size = 449 Mb, N50 = 26.78 Mb mainly on 17 pseudomolecules). Unique genomic features, patterns of gene regulation, and defence systems in millipedes, not observed in other arthropods, are revealed. Both repeat content and intron size are major contributors to the observed differences in millipede genome size. Tight Hox and the first loose ecdysozoan ParaHox homeobox clusters are identified, and a myriapod-specific genomic rearrangement including Hox3 is also observed. The Argonaute (AGO) proteins for loading small RNAs are duplicated in both millipedes, but unlike in insects, an AGO duplicate has become a pseudogene. Evidence of post-transcriptional modification in small RNAs-including species-specific microRNA arm switching-providing differential gene regulation is also obtained. Millipedes possesses a unique ozadene defensive gland unlike the venomous forcipules found in centipedes. We identify sets of genes associated with the ozadene that play roles in chemical defence as well as antimicrobial activity. Macro-synteny analyses revealed highly conserved genomic blocks between the 2 millipedes and deuterostomes. Collectively, our analyses of millipede genomes reveal that a series of unique adaptations have occurred in this major lineage of arthropod diversity. The 2 high-quality millipede genomes provided here shed new light on the conserved and lineage-specific features of millipedes and centipedes. These findings demonstrate the importance of the consideration of both centipede and millipede genomes-and in particular the reconstruction of the myriapod ancestral situation-for future research to improve understanding of arthropod evolution, and animal evolutionary genomics more widely.

Dataset Information

Platypus and echidna genomes reveal mammalian biology and evolution.

Publications

Platypus and echidna genomes reveal mammalian biology and evolution.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets