Physiologia Plantarum 133: 298–317. 2008 Copyright ª Physiologia Plantarum 2008, ISSN 0031-9317 Expressed sequence tag analysis of the response of apple (Malus x domestica ‘Royal Gala’) to low temperature and water deficit Michael Wisniewskia,*, Carole Bassetta,*, John Norellia, Dumitru Macarisina, Timothy Artlipa, Ksenija Gasicb and Schuyler Korbanb aUnited States Department of Agriculture – Agricultural Research Service (USDA-ARS), Appalachian Fruit Research Station, 2217 Wiltshire Road, Kearneysville, WV 25430, USA bDepartment of Natural Resources and Environmental Sciences, University of Illinois, 310 ERML, 1201 W. Gregory Drive, Urbana, IL 61801, USA Correspondence Leaf, bark, xylem and root tissues were used to make nine cDNA libraries from *Corresponding author, non-stressed (control) ‘Royal Gala’ apple trees, and from ‘Royal Gala’ trees e-mail:
[email protected]; exposed to either low temperature (5°C for 24 h) or water deficit (45% of
[email protected] saturated pot mass for 2 weeks). Over 22 600 clones from the nine libraries # Received 26 September 2007; revised 3 were subjected to 5 single-pass sequencing, clustered and annotated using January 2008 BLASTX. The number of clusters in the libraries ranged from 170 to 1430. Regarding annotation of the sequences, BLASTX analysis indicated that within doi: 10.1111/j.1399-3054.2008.01063.x the libraries 65–72% of the clones had a high similarity to known function genes, 6–15% had no functional assignment and 15–26% were completely novel. The expressed sequence tags were combined into three classes (control, low-temperature and water deficit) and the annotated genes in each class were placed into 1 of 10 different functional categories.