Anthocyanin accumulation

Many herbicides and other chemicals have been reported to influence levels of various phenolic compounds in higher plants by unknown mechanisms. It is unlikely that more than a few of these compounds have a primary influence on secondary phenolic compound synthesis. For instance, in our survey of the effects of 17 herbicides on anthocyanin accumulation, only glyphosate appeared to directly influence accumulation (31). The effects of several compounds on secondary phenolic compound production for which the mechanism of influence is unknown are summarized in Table II. A much longer list could be derived from the literature. Unfortunately, many of these compounds are phytotoxic or are known to have effects other than on secondary aromatic compound production. In most cases the effects on these compounds correlate well with extractable PAL activity (31, 71, 72, 73, 74) (Figure 5), even though they do not directly affect the enzyme. 

OVER-EXPRESSION OF PAP2, ANOTHER MYB GENE, ENHANCES ANTHOCYANIN ACCUMULATION... 

Lo Piero AR, Puglisi I, Rapisarda P, Petrone G (2005) Anthocyanins accumulation and related gene expression in red orange fruit induced by low temperature storage. J Agric Food Chem 53(23) 9083-9088... 

Borovsky Y, Oren-Shamir M, Ovadia R, De Jong W, Paran I (2004) The A locus that controls anthocyanin accumulation in pepper encodes a MYB transcription factor homologous to Anthocyaninl of Petunia. Theor Appl Genet 109 23-29... 

DC085 Han, A., K. P. Zanewich, S. B. Rood, and D. K. Dougall. Gibberellic acid decreases anthocyanin accumulation DC095 in wild carrot cell suspension cultures but does not alter 3 nucleosidase activity. Physiol Plant 1994 92(1) ... 

Hipskind, J., Wood, K., and Nicholson, R.L., Localized stimulation of anthocyanin accumulation and delineation of pathogen ingress in maize genetically resistant to Bipolaris maydis race O, Physiol Mol Plant Pathol, 49, 247, 1996. 

There is also a preliminary report of a P. frutescens cDNA encoding a membrane protein of unknown function (8R6) that promotes anthocyanin uptake into protoplasts and anthocyanin accumulation when overexpressed in A. thaliana transgenics.Within the vacuole of some plants (but not A. thaliana) the anthocyanins may occur in protein containing bodies, termed anthocyanic vacuolar inclusions (AVIs), whose function is as yet unknown but may relate to transport activities. ... 

Lo, S.C.C. and Nicholson, R.L., Reduction of light-induced anthocyanin accumulation in inoculated sorghum mesocotyls. Implications for a compensatory role in the defense response. Plant Physiol, 116, 979, 1998. 

Maekawa, M. et al.. Differential responses to UV-B irradiation of three near isogenic lines carrying different purple leaf genes for anthocyanin accumulation in rice Oryza sativa L.), Breeding Sci., 51, 27, 2001. 

Pietrini F., lanelli, M.A., and Massacci, A., Anthocyanin accumulation in the illuminated surface of maize leaves enhances protection from photo-inhibitory risks at low temperature, without further limitation to photosynthesis. Plant Cell Environ., 25, 1251, 2002. 

Baker, D.C. et al.. Effects of supplied cinnamic-acids and biosynthetic intermediates on the anthocyanins accumulated by wild carrot suspension-cultures. Plant Cell Tis. Organ Cult., 39, 79, 1994. 

Leng P, Itamura H, Yamamura H, Deng XM. 2000. Anthocyanin accumulation in apple and peach shoots during cold acclimation. Sci Hortic 83 43-50. 

Li XJ, Hou JH, Zhangb GL, Liu RS, Yang YG, Hu YX, Lin JX. 2004. Comparison of anthocyanin accumulation and morpho-anatomical features in apple skin during color formation at two habitats. Sci Hortic 99 41-53. 

WD-reoeat TTG1 PA and anthocyanin accumulation Walker et al, 1999, Gonzalez et al, 2008... 

Bailly C, Cormier F, Do CB. 1997. Characterization and activities of S-adenosyl-L-methionine cyanidin 3-glucoside 3 -0-methyltransferase in relation to anthocyanin accumulation in Vitis vinifera cell suspension cultures. Plant Sci 122 81-89. 

R2R3 MYB and HLH transcription factors acting in concert (Table 3.1). More recently, proteins containing conserved WD40 repeats have been implicated in the regulation of flavonoid biosynthesis as well. Thus, it is by variations of the combination of MYB/HLH/WD factors that anthocyanin accumulation is controlled (Table 3.1). 

Color perception can also be influenced by the physical properties of the cells where anthocyanins accumulate. An example is provided by the effect of the Mixta gene in snapdragon, which controls conical cell shape. Petal cells lacking Mixta function are palely pigmented because of the way light reflects, which could have significant consequences in the ways pollinators are attracted.68... 

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