|Richart, Gregory - PENNSYLVANIA STATE UNIV|
|Farrell, Robert - PENNSYLVANIA STATE UNIV|
Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: March 28, 2007
Publication Date: July 16, 2007
Citation: Bassett, C.L., Richart, G.A., Wisniewski, M.E., Artlip, T.S., Farrell, R.E. 2007. Mapping transcript start sites for three peach (Prunus persica L., Batsch) dehydrins: differences in transcript initiation during fruit development. HortScience. 42:876. Technical Abstract: A number of stress-responsive genes are expressed during fruit ripening in several different crops, including tomato, pepper, grape, and peach. In peach, a dehydrin shown to be up-regulated in bark in response to cold, PpDhn3, was also found to be highly abundant in ripe fruit. Two other dehydrins expressed primarily in young fruit were also detected in ripe fruit. Like PpDhn3, PpDhn1 is up-regulated in bark and leaves in response to cold, whereas, PpDhn2 responds to water deficit. Both PpDhn1 and 2 show differences in transcript initiation in young fruit compared to fully ripe fruit. PpDhn1 transcripts initiate at multiple positions in 7-day-old fruit much further upstream than the transcript start site in bark or in older fruit. In contrast, PpDhn2 transcripts initiate at several positions upstream of the bark transcript start site in fully ripe (137-day-old) fruit, while transcripts in younger fruit initiate at the same position as bark transcripts. Transcripts encoding PpDhn3 initiate at the same position in bark, and fruit of all stages examined. The biological significance of multiple start sites for PpDhn1 and 2 transcripts is unclear at present, although, there is evidence for an intron in the 5’ leader of the longer PpDhn2 transcripts. Possible functional consequences of the longer PpDhn2 leader will be discussed.