Identification of differentially expressed genes in potato associated with tuber dormancy release.

Potato (Solanum tuberosum L.) tuber dormancy and sprouting is very important to potato cultivation and processing. In the present experiment, suppression subtractive hybridization was employed to identify differentially expressed genes in potato associated with tuber dormancy release. 576 random clones were selected from subtractive library and successfully sequenced. A total of 304 effective expressed sequence tags (ESTs) were obtained ultimately. The ESTs have been deposited in the EMBL\GenBank\DDBJ nucleotide sequence data libraries under accession numbers from JK483901 to JK484204. GO annotation showed that 45, 34 and 3 % ESTs were associated with binding, catalytic activity and signaling respectively, some of which were confirmed to be involved in plant dormancy breaking, however, 14 % of the ESTs did not show significant homology to any database proteins. A real-time quantitative PCR (RT-qPCR) analysis of the expression patterns of 14 selectable transcripts showed that 13 selected candidate genes were significantly up-regulated in the development process of tuber from dormancy to sprouting. A full length cDNA of ADP-ribosylation factor (ARF) gene was cloned and found it belonged to potato ARF1 gene. Tissue specific expression analysis showed ARF1 expression level was the highest in tuber. RT-qPCR analysis of the expression profile of ARF1 gene from potato tuber dormancy to sprouting revealed that the ARF1 gene expression was significantly increased after tuber dormancy breaking, which suggested that it probably associated with tuber dormancy and sprouting.