Author
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Lulai, Edward |
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Neubauer, Jonathan |
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Submitted to: American Journal of Potato Research
Publication Type: Abstract Only Publication Acceptance Date: 4/14/2014 Publication Date: 4/4/2015 Citation: Lulai, E.C., Neubauer, J. 2015. The coordinate induction of DNA synthesis after tuber wounding [Abstract.] American Journal of Potato Research. 92:198. Interpretive Summary: Technical Abstract: Tuber wounding induces a cascade of biological responses involved in processes required to heal and protect surviving plant issues. Little is known about the coordination of these processes, including essential wound-induced DNA synthesis, yet they play critical roles in maintaining marketability of the harvested crop and tubers cut for seed. A modern “Click-iT EdU Assay” employing incorporation of the thymidine analog, 5-ethynyl-2’-deoxyuridine (EdU), in conjunction with 4’,6-diamindino-2-phenylindole (DAPI) counter labeling was employed to identify and determine the time course and spatial distribution of tuber nuclei that were wound-induced to enter S-phase of the cell cycle; a critical, but neglected part, of wound-healing. Both labeling procedures are rapid and sensitive in situ. Following wounding, EdU incorporation (indicating DNA synthesis) was not initiated until after 12 h, rapidly reached a maximum at about 18 h and then declined to near zero at 48 h. About 28 % of the nuclei were EdU labeled at 18 h reflecting the proportion of cells in S-phase of the cell cycle. During the 36 h in which induced cells were progressing through S-phase, de novo DNA synthesis extended 7 to 8 cell layers below the wound surface. Termination of nuclear DNA synthesis occurred about 4 d prior to completion of wound closing layer formation and initiation of wound periderm development; a time at which meristematic activity may be detected via the production of new phellem cells. Collectively, these results provide new insight into the coordination of cellular processes involved in tuber wound-healing. |
