Transcriptional regulation of a pineapple polyphenol oxidase gene and its relationship to blackheart

Zhou, Yuchan, O'Hare, Tim J., Jobin-Decor, Marcelle, Underhill, Steven J. R., Wills, Ron B. H. and Graham, Michael W. (2003) Transcriptional regulation of a pineapple polyphenol oxidase gene and its relationship to blackheart. Plant Biotechnology Journal, 1 6: 463-478. doi:10.1046/j.1467-7652.2003.00042.x

Author Zhou, Yuchan
O'Hare, Tim J.
Jobin-Decor, Marcelle
Underhill, Steven J. R.
Wills, Ron B. H.
Graham, Michael W.
Title Transcriptional regulation of a pineapple polyphenol oxidase gene and its relationship to blackheart
Journal name Plant Biotechnology Journal   Check publisher's open access policy
ISSN 1467-7644
Publication date 2003-11
Sub-type Article (original research)
DOI 10.1046/j.1467-7652.2003.00042.x
Open Access Status
Volume 1
Issue 6
Start page 463
End page 478
Total pages 16
Place of publication Oxford, United Kingdom
Publisher Wiley-Blackwell Publishing
Language eng
Formatted abstract
Two genes encoding polyphenol oxidase (PPO) were isolated from pineapple (Ananas comosus[L.] Merr. cv. Smooth Cayenne). Sequence analyses showed that both contained a single intron and encoded typical chloroplast-localized PPO proteins, the sequences of which corresponded to two pineapple PPO cDNAs, PINPPO1 and PINPPO2, recently described by Stewart et al. (2001). Southern blot analyses suggested that pineapple contained only two PPO genes. Analysis of expression of PINPPO1 promoter GUS fusion constructs showed this promoter had a low basal activity and was cold- and wound-inducible, consistent with known mRNA expression profiles. Striking homologies to gibberellin response complexes (GARC) were observed in sequences of both the PINPPO1 and PINPPO2 promoters. Transient assays in mature pineapple fruit and stable expression in transgenic tobacco showed that PINPPO1 promoter-GUS fusions were indeed gibberellin (GA) responsive. A role for the element within the putative GARCs in mediating GA-responsiveness of the PINPPO1 promoter was confirmed by mutational analysis. PINPPO2 was also shown to be GA-responsive by RT-PCR analysis. Mutant PINPPO1 promoter–GUS fusion constructs, which were no longer GA-inducible, showed a delayed response to cold induction in pineapple fruit in transient assays, suggesting a role for GA in blackheart development. This was supported by observations that exogenous GA3 treatment induced blackheart in the absence of chilling. Sequences showing homology to GARCs are also present in some PPO promoters in tomato, suggesting that GA regulates PPO expression in diverse species.
Keyword Blackheart
Gene regulation
Polyphenol oxidase
Green fluorescent protein
Barley aleurone cells
Alpha-amylase Gene
Promoter elements
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collection: Queensland Alliance for Agriculture and Food Innovation
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Citation counts: TR Web of Science Citation Count  Cited 21 times in Thomson Reuters Web of Science Article | Citations
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Created: Mon, 07 Mar 2011, 15:21:40 EST