Transcriptomic profiling of fruits of four raspberry cultivars with different pigmentation
Transcriptomic profiling of fruits of four raspberry cultivars with different pigmentation
Developing fruits of the raspberry cultivars 'Anitra', 'Glen Ample', 'Varnes' and 'Veten' were collected at three maturity stages; (1) unripe (at 25 days post-anthesis), (2) turning (at 30 days post anthesis), and (3) fully mature (35 days post anthesis). Fruit samples from each cultivar at each maturity stage were divided into 3 biological replicates, each with 15 berries with stage-representative characteristics. The berries were frozen in liquid nitrogen and kept at – 80 °C until further processing. The plants were maintained in a growth room at a constant temperature of 24 °C during the day and 18 °C at night, with a 16-hour photoperiod Tissue samples were ground to a fine powder under liquid nitrogen, and total RNA was extracted using the RNeasy Plant Mini Kit (Qiagen, Oslo, Norway) following the manufacturer's instructions. The concentration and purity of the resultant RNA was measured using a QIAxpert spectrophotometer (Qiagen, Oslo, Norway) and the integrity of the RNA was determined using a Qubit 4.0 fluorimeter (Thermo Fisher Scientific, Dartford, UK). Samples with an RNA integrity number (RIN) value above 7.0 were submitted for subsequent library preparation and sequencing. Library preparation was performed for the 36 fruit samples using the NEB Next® ultra RNA library prep kit (Biolabs, Inc., Beijing, China).