2 ml reaction tube

Cultures were transferred from standard growth conditions at 12 °C and 100 µmol photons m⁻² s⁻¹ to 2, 12, 22 and 32 (±1) °C for one week at 100 and 500 µmol photons m⁻² s⁻¹ (n = 8) in a light:dark cycle of 16:8 in a Multi-Cultivator MC 1000-OD (Photon Systems Instruments, Brno, Czech Republic). Additionally, algae were cultured at 2 °C in darkness for one week. Sampling was performed initially (1 h), short-term (16 h) and long-term (1 week), replicates n = 8. An external cooling aggregate was mounted to the MC for the treatments at 2 and 12 °C. Exposures to UV-radiation (UVR) were performed short-term (16 h) at all mentioned temperatures for high and low light (500 and 100 µmol photons m⁻² s⁻¹) exposure in a sun simulator (SonSi, iSiTECGmbH, Bremerhaven, Germany). For a solar-like spectrum including UVR (UVA 8.8 Wm⁻², UVB 0.61 W m⁻²), the cultures were illuminated with a 400 W Metallogen lamp (Philips MSR 400 HR, Germany), as described in literature^{29 (link),30 (link)}. After exposure, samples from all treatments were collected. Additionally, samples from standard culture conditions and from one day, one week and one month old cultures (n = 3) were taken. Samples were centrifuged in 2 mL reaction tubes (Sarstedt, Nümbrecht, Germany) for 10 s, the liquid phase was discarded. The tubes were initially flash-frozen in liquid nitrogen and stored at −80 °C until RNA extraction.

Fresh material (200 mg) from selected transgenic HRs grown on solid MS20 medium was transferred to 2-mL reaction tubes (Sarstedt, Nümbrecht, Germany) and powdered by means of metal balls in liquid nitrogen in a Mixer Mill MM 400 (Retsch, Haan, Germany) at a frequency of 30/s for 1 min. The powder was extracted in 1 mL perchloric acid (5%, v/v) containing 2 nmol 1,7-diaminoheptane as an internal standard under freeze-thaw cycles according to Minocha et al. [87 (link)]. Subsequently, the pH was raised to pH 9–10 with 10 M NaOH (approx. 50 μL per 1000 μL extract). Precolumn derivatization and chromatography of polyamines were carried out according to Kaltenegger et al. [88 (link)] using a fluorescence detector (Figure A1).

7.5 × 10⁵ human T cells were transferred in RPMI 1640 medium into a 2 mL reaction tube (Sarstedt, Nümbrecht, Germany). Each reaction tube was treated with a single dose in the range from 2 to 50 Gy as indicated in the respective Figures using the Gammacell^® 3000 Elan (Nordion International Inc., Ottawa, ON, Canada).