Paulinella micropora KR01 holobiont genome assembly for studying primary plastid evolution

Lhee, D.; Lee, J.; Cho, C. H.; Ha, J.-S.; Jeong, S. E.; Jeon, C. O.; Zelzion, U.; Price, D. C.; Chan, Y.-F.; Gabr, A.; Bhattacharya, D.; Yoon, H. S.

doi:10.1101/794941

bioRxiv · 10.1101/794941

Paulinella micropora KR01 holobiont genome assembly for studying primary plastid evolution

Lhee, D.·Lee, J.·Cho, C. H.·Ha, J.-S.·Jeong, S. E.·Jeon, C. O.·Zelzion, U.·Price, D. C.·Chan, Y.-F.·Gabr, A.·Bhattacharya, D.·Yoon, H. S.

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Abstract

The widespread algal and plant (Archaeplastida) plastid originated >1 billion years ago, therefore relatively little can be learned about plastid integration during the initial stages of primary endosymbiosis by studying these highly derived species. Here we focused on a unique model for endosymbiosis research, the photosynthetic amoeba Paulinella micropora KR01 (Rhizaria) that underwent a more recent independent primary endosymbiosis about 124 Mya. A total of 149 Gbp of PacBio and 19 Gbp of Illumina data were used to generate the draft assembly that comprises 7,048 contigs with N50=143,028 bp and a total length of 707 Mbp. Genome GC-content was 44% with 76% repetitive sequences. We predicted 32,358 genes that contain 73% of the complete, conserved genes in the BUSCO database. The mean intron length was 882 bp, which is significantly greater than in other Rhizaria (86[~]184 bp). Symbiotic bacteria from the culture were isolated and completed genomes were generated from three species (Mesorhizobium amorphae Pch-S, Methylibium petroeiphilum Pch-M, Polaromonas sp. Pch-P) with one draft genome (Pimelobacter simplex Pch-N). Our holobiont data establish P. micropora KR01 as a model for studying plastid integration and the role of bacterial symbionts in Paulinella biology.

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Lhee, D., Lee, J., Cho, C. H., Ha, J.-S., Jeong, S. E., Jeon, C. O., Zelzion, U., Price, D. C., Chan, Y.-F., Gabr, A., Bhattacharya, D., Yoon, H. S.. 2019-10-07. Paulinella micropora KR01 holobiont genome assembly for studying primary plastid evolution. https://doi.org/10.1101/794941

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