Gene expression profiling and identification of resistance genes to low temperature in leaves of peanut (Arachis hypogaea L.)

• We identified genes regulated by cold stress in peanut using microarray technique.
• Possible functions of the cold-regulated genes were analyzed.
• This article attempts an overview of transcription map of peanut under cold stress.
• This article offers some candidate genes responded to cold stress in peanut.

The cultivated peanut (Arachis hypogaea L.) is important oil crop and cold stress seriously influences its development and yields. Tolerant varieties produced using transgenic techniques will effectively increase peanut plantation area and enhance yields. However, little is known about the network of gene expression regulation related to cold stress in peanut. Therefore, we screened genes regulated by cold stress in peanut. In total, 1478 up-regulated and 1510 down-regulated probe sets were successfully identified in leaves of peanut subjected to cold stress using the microarray technique. Data analysis indicated that the main biological processes involved in cold stress response included signal transduction, transcript regulations and accumulation of soluble metabolites. Regulation of cell division, translation, protein modification, transport and DNA/RNA-related processes were also involved in peanut cold acclimation. Our study also revealed that protein kinases, transcription factors, heat shock proteins, resistance proteins, stilbene synthase, and so on, may play important functions in cold stress regulation of peanut. The function of some probe sets in cold stress regulation had not been clarified (e.g. proteins functioning in glycerol ether metabolic process, microtubule-based movement or nutrient reservoir activity). Some genes we identified lack functional annotation and their roles in response to cold are yet to be elucidated. These results showed an overview of the transcription map of peanut under cold stress, which may yield some useful insights into cold-mediated signal transduction pathways in peanut and offer some candidate genes as potential markers of tolerance to cold stress.