PT  - JOURNAL ARTICLE
AU  - Katherine Dougan
AU  - Zhi-Luo Deng
AU  - Lars Wöhlbrand
AU  - Carsten Reuse
AU  - Boyke Bunk
AU  - Yibi Chen
AU  - Juliane Hartlich
AU  - Karsten Hiller
AU  - Uwe John
AU  - Jana Kalvelage
AU  - Johannes Mansky
AU  - Meina Neumann-Schaal
AU  - Jörg Overmann
AU  - Jörn Petersen
AU  - Selene Sanchez
AU  - Kerstin Schmidt-Hohagen
AU  - Sarah Shah
AU  - Cathrin Spröer
AU  - Helena Sztajer
AU  - Hui Wang
AU  - Debashish Bhattacharya
AU  - Ralf Rabus
AU  - Dieter Jahn
AU  - Cheong Xin Chan
AU  - Irene Wagner-Döbler
TI  - Evolution of resilience against heat stress in a red-tide dinoflagellate
AID  - 10.1101/2022.07.25.501386
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.07.25.501386
4099  - http://biorxiv.org/content/early/2022/07/25/2022.07.25.501386.short
4100  - http://biorxiv.org/content/early/2022/07/25/2022.07.25.501386.full
AB  - Dinoflagellates are a large, ecologically important phylum of marine unicellular algae. Their huge genomes make it highly challenging to decipher the genetic basis of key processes such as harmful algal bloom (HAB) formation and response to warming oceans. To address these issues, we generated a high quality genome assembly from Prorocentrum cordatum, a globally abundant, HAB forming dinoflagellate. Our analyses demonstrate massive expansion of the gene inventory to 85,849 predicted genes, primarily driven by unusually long and frequent introns and dispersed duplicates enriched for bloom relevant functions. We find that cell yield is reduced at higher culture temperatures. To understand this response, we integrated transcriptome, proteome and metabolome data and identified both a global and a temperature specific heat-stress response. The underlying metabolic changes reflect damage to photosynthesis and central metabolism. The transcriptome data show that ∼25% of genes are differentially expressed under heat stress, with concomittant extensive RNA editing and alternative exon usage. Multi-codon genes and transcripts for HSP70 and RuBisCo suggest a polycistronic gene organisation. Our work represents the first genome based analysis of a red tide dinoflagellate and demonstrates that temperature resilience in P. cordatum is mediated by a unique genome structure and multi-level transcriptional regulation.Competing Interest StatementThe authors have declared no competing interest.