MAX1 Encodes a Cytochrome P450 Family Member that Acts Downstream of MAX3/4 to Produce a Carotenoid-Derived Branch-Inhibiting Hormone

Booker, Jonathan; Sieberer, Tobias; Wright, Wendy; Williamson, Lisa; Willett, Barbara; Stirnberg, Petra; Turnbull, Colin; Srinivasan, Murali SrinivasanM.; Goddard, Peter; Leyser, Ottoline

doi:10.1016/j.devcel.2005.01.009

Cited by 484 publications

(467 citation statements)

References 31 publications

Supporting

Mentioning

439

Contrasting

Unclassified

Order By: Relevance

“…cells, through which auxin is transported down the stem (Morris and Thomas, 1978). AXR1 and strigolactone biosynthesis genes are indeed known to be expressed in those cells (Booker et al, , 2005Sorefan et al, 2003). Whereas AXR1 may have additional targets, TIR1 is thought to more directly affect auxin responses.…”

Section: Discussionmentioning

confidence: 99%

“…Mutant phenotypes were rescued by grafting with wild-type tissue, even in interstock grafts where small pieces of wild-type stem tissue were grafted between mutant rootstock and shoot tissue (Napoli, 1996;Foo et al, 2001). Other mutants were not rescued by grafting but were instead suggested to lack response to SMS (Beveridge et al, 1996;Booker et al, 2005). Grafting studies also showed that outgrowth induced by decapitation in SMS mutant plants cannot be inhibited by IAA applied to the stump unless a wild-type rootstock is present .…”

mentioning

confidence: 99%

See 1 more Smart Citation

Strigolactone Acts Downstream of Auxin to Regulate Bud Outgrowth in Pea and Arabidopsis

et al. 2009

View full text Add to dashboard Cite

During the last century, two key hypotheses have been proposed to explain apical dominance in plants: auxin promotes the production of a second messenger that moves up into buds to repress their outgrowth, and auxin saturation in the stem inhibits auxin transport from buds, thereby inhibiting bud outgrowth. The recent discovery of strigolactone as the novel shootbranching inhibitor allowed us to test its mode of action in relation to these hypotheses. We found that exogenously applied strigolactone inhibited bud outgrowth in pea (Pisum sativum) even when auxin was depleted after decapitation. We also found that strigolactone application reduced branching in Arabidopsis (Arabidopsis thaliana) auxin response mutants, suggesting that auxin may act through strigolactones to facilitate apical dominance. Moreover, strigolactone application to tiny buds of mutant or decapitated pea plants rapidly stopped outgrowth, in contrast to applying N-1-naphthylphthalamic acid (NPA), an auxin transport inhibitor, which significantly slowed growth only after several days. Whereas strigolactone or NPA applied to growing buds reduced bud length, only NPA blocked auxin transport in the bud. Wild-type and strigolactone biosynthesis mutant pea and Arabidopsis shoots were capable of instantly transporting additional amounts of auxin in excess of endogenous levels, contrary to predictions of auxin transport models. These data suggest that strigolactone does not act primarily by affecting auxin transport from buds. Rather, the primary repressor of bud outgrowth appears to be the auxindependent production of strigolactones.

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Strigolactone Acts Downstream of Auxin to Regulate Bud Outgrowth in Pea and Arabidopsis

et al. 2009

View full text Add to dashboard Cite

show abstract

“…1) produce carlactone (Alder et al 2012). Carlactone (or another derived intermediate) is then transported to the cytosol where it is possibly converted to strigolactones by MAX1 that encodes a cytoplasmic cytochrome P450 enzyme (Booker et al 2005;Waters et al 2012). …”

Section: Introductionmentioning

confidence: 99%

Strigolactones fine-tune the root system

Rasmussen

Depuydt

Goormachtig

et al. 2013

Planta

View full text Add to dashboard Cite

Strigolactones were originally discovered to be involved in parasitic weed germination, in mycorrhizal association and in the control of shoot architecture. Despite their clear role in rhizosphere signaling, comparatively less attention has been given to the belowground function of strigolactones on plant development. However, research has revealed that strigolactones play a key role in the regulation of the root system including adventitious roots, primary root length, lateral roots, root hairs and nodulation. Here, we review the recent progress regarding strigolactone regulation of the root system and the antagonism and interplay with other hormones

show abstract

“…Recent studies on a series of branching mutants, such as more axillary growth (max) of Arabidopsis [37][38][39][40], ramosus (rms) mutants of pea [41][42][43], decreased apical dominance (dad) mutants of petunia [44,45] and dwarf (d) mutants of rice [46][47][48][49][50][51], have revealed strigolactone as a second messenger of auxin action on the control of AM outgrowth [52,53]. Strigolactones, a group of terpenoid lactones that have been found in root exudates of diverse plant species, are synthesized from carotenoids in roots and transported acropetally or synthesized locally to repress the outgrowth of shoot branches [38,[54][55][56].…”

Section: Introductionmentioning

confidence: 99%

The BUD2 mutation affects plant architecture through altering cytokinin and auxin responses in Arabidopsis

et al. 2010

View full text Add to dashboard Cite

The ratio of auxin and cytokinin plays a crucial role in regulating aerial architecture by promoting or repressing axillary bud outgrowth. We have previously identified an Arabidopsis mutant bud2 that displays altered root and shoot architecture, which results from the loss-of-function of S-adenosylmethionine decarboxylase 4 (SAMDC4). In this study, we demonstrate that BUD2 could be induced by auxin, and the induction is dependent on auxin signaling. The mutation of BUD2 results in hyposensitivity to auxin and hypersensitivity to cytokinin, which is confirmed by callus induction assays. Our study suggests that polyamines may play their roles in regulating the plant architecture through affecting the homeostasis of cytokinins and sensitivities to auxin and cytokinin. IntroductionPolyamines, including diamine putrescine, triamine spermidine and tetraamine spermine, are low-molecularmass organic cations. They exist widely in all living organisms and are essential for their survival, because blocking of the biosynthesis of polyamines leads to lethal phenotypes in animals [1] and higher plants [2][3][4]. In higher plants, polyamines have been proposed to function in response to environmental stresses and in regulating growth and development [4][5][6][7][8][9][10][11]. Plant molecular and physiological studies over past decades have shown that higher plants defective in producing polyamines often have altered plant architecture, with reduced plant height or more branches in shoots and roots [4,[10][11][12][13]. However, the underlying mechanisms still remain largely elusive.Branches of higher plants originate from the axillary meristems (AMs) of shoots, and formation of a branch generally consists of the initiation of a new AM and its subsequent outgrowth. However, an AM may arrest its growth under some conditions, forming a dormant bud. The dormant buds will release their outgrowth once they sense a permissible environmental or developmental signal. In many plant species, axillary buds become dormant due to the inhibiting effects of the primary shoot apex on the outgrowth of AMs, a phenomenon known as 'apical dominance'. Auxin was first regarded as a direct regulator in this process [14], a notion strengthened thereafter by physiological studies on decapitated shoot apices [15][16][17], and by analyzing auxin biosynthesis, transport and signaling [18][19][20][21][22][23][24][25][26][27][28][29] in plants. However, when radiolabelled auxin was applied to a decapitated stump, the outgrowth of axillary buds was inhibited even though radiolabelled auxin was not found to accumulate in axillary buds, suggesting an indirect suppression effect of auxin on the AM outgrowth [28,30] and the presence of second messengers.Cytokinin has been proposed as a second messenger that mediates the action of auxin in controlling the apical dominance, because it promotes the outgrowth of lateral buds when directly applied to buds [31]. Although an antagonistic role of auxin and cytokinin in the regulation of apical dominance has been postu...

show abstract

MAX1 Encodes a Cytochrome P450 Family Member that Acts Downstream of MAX3/4 to Produce a Carotenoid-Derived Branch-Inhibiting Hormone

Cited by 484 publications

References 31 publications

Strigolactone Acts Downstream of Auxin to Regulate Bud Outgrowth in Pea and Arabidopsis

Strigolactone Acts Downstream of Auxin to Regulate Bud Outgrowth in Pea and Arabidopsis

Strigolactones fine-tune the root system

The BUD2 mutation affects plant architecture through altering cytokinin and auxin responses in Arabidopsis

Contact Info

Product

Resources

About