Laboratory studies were carried out at the University of Georgia, Athens, GA, USA. The studies took place over the following dates:
Thalassiosira: 1-7th July 2020
Synechococcus: 16-23rd Feb 2021
Emiliania: 18-28th May 2021

Emiliania huxleyi CCMP151
A laboratory study was conducted using cultures of a marine coccolithophore (Emiliania huxleyi CCMP151) and heterotrophic bacterium, Ruegeria pomeroyi. Coccolithophore cultures were pre-acclimated to three temperature treatments (15°, 20°, and 28° Celsius) and grown co-cultures. The transcriptome treatments consisted of axenic coccolithophore, the coccolithophore with the bacterium, and the bacterium with the coccolithophore, and three replicates were analyzed at each sample point. Stranded RNA-Seq libraries were sequenced using an Illumina NovaSeq instrument. For co-cultures, E. huxleyi and bacterial cells were separated by filtration prior to RNA extraction.

Thalassiosira pseudonana CCMP1335
A laboratory study was conducted using cultures of a marine diatom (Thalassiosira pseudonana CCMP1335) and heterotrophic bacterium, Ruegeria pomeroyi. Diatom cultures were pre-acclimated to three temperature treatments (14°, 20°, and 28° Celsius) and grown as co-cultures. The transcriptome treatments consisted of axenic diatom, the diatom with the bacterium, and the bacterium with the diatom, and three replicates were analyzed at each sample point. Stranded RNA-Seq libraries were sequenced using an Illumina NovaSeq instrument. For co-cultures, diatom and bacterial cells were separated by filtration prior to RNA extraction.

Synechococcus sp. WH8102
A laboratory study was conducted using cultures of a marine cyanobacterium (Synechococcus sp. WH8102 and heterotrophic bacterium, Ruegeria pomeroyi. Synechococcus cultures were pre-acclimated to three temperature treatments (20°, 24°, and 28° Celsius) and grown as co-cultures. The transcriptome treatments consisted of axenic Synechococcus, Synechococcus with the heterotrophic bacterium, and the bacterium with the Synechococcus, and three replicates were analyzed at each sample point. Stranded RNA-Seq libraries were sequenced using an Illumina NovaSeq instrument. RNA extraction of co-cultures was carried out without prefiltration, and transcripts were separated at mapping.