Transcriptome analysis of celery under limited calcium supply

Transcriptome of celery (Apium graveolens) under limited calcium (Ca) supply was analyzed by RNA sequencing, with the aim of understanding the impacts of Ca deficiency on plant metabolism. Young seedlings of celery (Apium graveolens L. cv. Matsumoto No. 1) were obtained from a producer in Nagano Prefecture, Japan, and cultured hydroponically in a culture room maintained at 25 degree C and 16/8 h light/dark cycle. The medium contained 1 mM Ca(NO3)2, 1 mM KCl, 0.5 mM MgSO4, 0.25 mM (NH4)2HPO4, 100 µM Fe(III)EDTA, 46 µM B(OH)3, 9 µM MnCl2, 0.8 µM ZnSO4, 0.3 µM CuSO4, and 0.1 µM (NH4)2Mo7O24. Two weeks after starting the hydroponic cultivation, the seedling were transferred to either control (the medium indicated above) or low Ca medium. The low Ca medium contained 0.1 mM Ca(NO3)2 and 1.8 mM KNO3. The uppermost leaves were sampled at 4 and 7 day after starting the treatment. Total RNA was extracted using an RNA extraction kit (RBC Bioscience).