European lancelet (Branchiostoma lanceolatum)

Lancelets are the modern survivors of an ancient chordate lineage, with a fossil record dating back to the Cambrian period. B. lanceolatum was originally found in shallow seas in the north-east Atlantic Ocean, but through the Suez Canal its range has expanded to the northerly parts of the Indian Ocean and the coasts of East Africa! Read more about European lancelets on Wikipedia.

africa-animal-big-cat-88234.jpg

Lancelet Branchiostoma lanceolatum, photo by Hans Hillewaert [CC BY-NC-ND 2.0], via flickr.com

Chromosome-length genome assembly

Download the Bl71nemr_HiC.fasta.gz file containing the chromosome-length (2n=38) assembly of the European lancelet genome. All modifications with respect to the draft (see below) are annotated in the Bl71nemr_HiC.assembly file. Some basic stats associated with the new reference, Bl71nemr_HiC, are listed below. The full data release can be explored here.

Contig length (bp)
Number of contigs
Contig N50 (bp)
Longest contig (bp)
474,881,800
91,317
11,312
117,503
Scaffold length (bp)
Number of scaffolds
Scaffold N50 (bp)
Longest scaffold (bp)
495,618,278
11,838
21,521,408
40,379,348
Draft

The chromosome-length genome assembly is based on the draft assembly Bl71nemr (GCA_900088365.1), credited below.

Marlétaz, F., Firbas, P.N., Maeso, I., Tena, J.J., Bogdanovic, O., Perry, M., Wyatt, C.D.R., de la Calle-Mustienes, E., Bertrand, S., Burguera, D., Acemel, R.D., van Heeringen, S.J., Naranjo, S., Herrera-Ubeda, C., Skvortsova, K., Jimenez-Gancedo, S., Aldea, D., Marquez, Y., Buono, L., Kozmikova, I., Permanyer, J., Louis, A., Albuixech-Crespo, B., Le Petillon, Y., Leon, A., Subirana, L., Balwierz, P.J., Duckett, P.E., Farahani, E., Aury, J.-M., Mangenot, S., Wincker, P., Albalat, R., Benito-Gutiérrez, È., Cañestro, C., Castro, F., D'Aniello, S., Ferrier, D.E.K., Huang, S., Laudet, V., Marais, G.A.B., Pontarotti, P., Schubert, M., Seitz, H., Somorjai, I., Takahashi, T., Mirabeau, O., Xu, A., Yu, J.-K., Carninci, P., Martinez-Morales, J.R., Crollius, H.R., Kozmik, Z., Weirauch, M.T., Garcia-Fernàndez, J., Lister, R., Lenhard, B., Holland, P.W.H., Escriva, H., Gómez-Skarmeta, J.L., Irimia, M., 2018. Amphioxus functional genomics and the origins of vertebrate gene regulation. Nature 564, 64-70. https://doi.org/10.1038/s41586-018-0734-6.

Method

3D Assembly was performed using 3D-DNA pipeline (Dudchenko et al., Science, 2017). The genome was reviewed using Juicebox Assembly Tools  (Dudchenko et al., bioRxiv, 2018). See Methods for more information.

Hi-C sample

The whole animal sample for in situ Hi-C preparation was obtained from Leonid Moroz, University of Florida. We thank Moroz for additional samples for this species.

Hi-C Contact maps

Hi-C data was aligned to the draft reference using Juicer (Durand, Shamim et al., Cell Systems, 2016), and contact maps visualizing the alignments with respect to the draft and the new reference were built using 3D-DNA (Dudchenko et al., Science, 2017). The contact maps can be explored below via Juicebox.js interactive tool (Robinson et al., Cell Systems, 2018). To explore the assembly in greater detail, please download the .hic and .assembly files from the data release folder and use Juicebox Assembly Tools  (Dudchenko et al., bioRxiv, 2018).

References

If you use this genome assembly in your research, please check that the conditions of use associated with the draft permit it, and acknowledge the following work.

Marlétaz, F., Firbas, P.N., Maeso, I., Tena, J.J., Bogdanovic, O., Perry, M., Wyatt, C.D.R., de la Calle-Mustienes, E., Bertrand, S., Burguera, D., Acemel, R.D., van Heeringen, S.J., Naranjo, S., Herrera-Ubeda, C., Skvortsova, K., Jimenez-Gancedo, S., Aldea, D., Marquez, Y., Buono, L., Kozmikova, I., Permanyer, J., Louis, A., Albuixech-Crespo, B., Le Petillon, Y., Leon, A., Subirana, L., Balwierz, P.J., Duckett, P.E., Farahani, E., Aury, J.-M., Mangenot, S., Wincker, P., Albalat, R., Benito-Gutiérrez, È., Cañestro, C., Castro, F., D'Aniello, S., Ferrier, D.E.K., Huang, S., Laudet, V., Marais, G.A.B., Pontarotti, P., Schubert, M., Seitz, H., Somorjai, I., Takahashi, T., Mirabeau, O., Xu, A., Yu, J.-K., Carninci, P., Martinez-Morales, J.R., Crollius, H.R., Kozmik, Z., Weirauch, M.T., Garcia-Fernàndez, J., Lister, R., Lenhard, B., Holland, P.W.H., Escriva, H., Gómez-Skarmeta, J.L., Irimia, M., 2018. Amphioxus functional genomics and the origins of vertebrate gene regulation. Nature 564, 64-70. https://doi.org/10.1038/s41586-018-0734-6.

Dudchenko, O., Batra, S.S., Omer, A.D., Nyquist, S.K., Hoeger, M., Durand, N.C., Shamim, M.S., Machol, I., Lander, E.S., Aiden, A.P., Aiden, E.L., 2017. De novo assembly of the Aedes aegypti genome using Hi-C yields chromosome-length scaffolds. Science 356, 92–95. https://doi.org/10.1126/science.aal3327.

Dudchenko, O., Shamim, M.S., Batra, S., Durand, N.C., Musial, N.T., Mostofa, R., Pham, M., Hilaire, B.G.S., Yao, W., Stamenova, E., Hoeger, M., Nyquist, S.K., Korchina, V., Pletch, K., Flanagan, J.P., Tomaszewicz, A., McAloose, D., Estrada, C.P., Novak, B.J., Omer, A.D., Aiden, E.L., 2018. The Juicebox Assembly Tools module facilitates de novo assembly of mammalian genomes with chromosome-length scaffolds for under $1000. bioRxiv 254797. https://doi.org/10.1101/254797.

Disclaimer

This is a work in progress. If you notice any discrepancies in the map or have data that confirms or contradicts the suggested reference, please email us at thednazoo@gmail.com or leave a comment on the Forum.