Control of Sucrose Biosynthesis

MacRae, Elspeth; Lunn, John E.

doi:10.1002/9781119312994.apr0224

Cited by 7 publications

(7 citation statements)

References 136 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The glucose and fructose formed by invertase can be phosphorylated to form hexose phosphates, contributing to the rise in Glc6P in short photoperiods or high irradiance. This metabolic cycle will decrease the net rate of sucrose synthesis, and the increase of hexose phosphates will trigger feedback inhibition of cFBP and stimulate starch synthesis (Huber ; Kingston‐Smith et al ; MacRae & Lunn ; Stitt et al ). In our experiments, the rise of glucose and fructose in the light period was more marked at higher irradiance and, at a given irradiance, was much more marked in short photoperiods compared to long photoperiods (Fig.…”

Section: Discussionmentioning

confidence: 99%

Photosynthate partitioning to starch in Arabidopsis thaliana is insensitive to light intensity but sensitive to photoperiod due to a restriction on growth in the light in short photoperiods

Mengin

Pyl

Moraes

et al. 2017

Plant Cell & Environment

109

View full text Add to dashboard Cite

Photoperiod duration can be predicted from previous days, but irradiance fluctuates in an unpredictable manner. To investigate how allocation to starch responds to changes in these two environmental variables, Arabidopsis Col-0 was grown in a 6 h and a 12 h photoperiod at three different irradiances. The absolute rate of starch accumulation increased when photoperiod duration was shortened and when irradiance was increased. The proportion of photosynthate allocated to starch increased strongly when photoperiod duration was decreased but only slightly when irradiance was decreased. There was a small increase in the daytime level of sucrose and twofold increases in glucose, fructose and glucose 6-phosphate at a given irradiance in short photoperiods compared to long photoperiods. The rate of starch accumulation correlated strongly with sucrose and glucose levels in the light, irrespective of whether these sugars were responding to a change in photoperiod or irradiance. Whole plant carbon budget modelling revealed a selective restriction of growth in the light period in short photoperiods. It is proposed that photoperiod sensing, possibly related to the duration of the night, restricts growth in the light period in short photoperiods, increasing allocation to starch and providing more carbon reserves to support metabolism and growth in the long night.

show abstract

Section: Discussionmentioning

confidence: 99%

Photosynthate partitioning to starch in Arabidopsis thaliana is insensitive to light intensity but sensitive to photoperiod due to a restriction on growth in the light in short photoperiods

Mengin

Pyl

Moraes

et al. 2017

Plant Cell & Environment

109

View full text Add to dashboard Cite

show abstract

“…Glyceraldehyde 3-phosphate and DHA phosphate are rapidly and reversibly interconverted by the enzyme triose phosphate isomerase (TPI), and are the key product exported by chloroplasts during photosynthesis. DHA phosphate is therefore a precursor to cytosolic production of hexose phosphates and sucrose in photosynthetic cells in the light ( MacRae and Lunn, 2006 ), and mānuka nectaries are green and photosynthetically active (M. Clearwater and S. Noe, University of Waikato, unpubl. res.).…”

Section: Discussionmentioning

confidence: 99%

Influence of genotype, floral stage, and water stress on floral nectar yield and composition of mānuka (Leptospermum scoparium)

et al. 2018

View full text Add to dashboard Cite

Background and AimsFloral nectar can be variable in composition, influencing pollinator behaviour and the composition of honey derived from it. The non-peroxide antibacterial activity of mānuka (Leptospermum scoparium, Myrtaceae) honey results from the chemical conversion of the triose sugar dihydroxyacetone (DHA), after DHA accumulates for an unknown reason in the nectar. This study examined variation in nectar DHA, glucose, fructose and sucrose content with floral stage of development, between mānuka genotypes with differing flower morphology, and in response to water stress.MethodsSix mānuka genotypes were grown without nectar-feeding insects. Stages of flower development were defined, nectar was harvested and its composition was compared between stages and genotypes, and with floral morphology. Water stress was imposed and its effect on nectar composition was examined.Key ResultsNectar was present from soon after flower opening until the end of petal abscission, with the quantity of accumulated nectar sugars rising, then stabilizing or falling, indicating nectar secretion followed by reabsorption in some genotypes. The quantity of DHA, the ratio of DHA to other nectar sugars and the fructose to glucose ratio also varied with stage of development, indicating differences in rates of production and reabsorption between nectar components. Nectar composition and yield per flower also differed between genotypes, although neither was positively related to nectary area or stomatal density. Drying soil had no effect on nectar composition or yield, but variation in nectar yield was correlated with temperature prior to nectar sampling.ConclusionsMānuka nectar yield and composition are strongly influenced by plant genotype, flower age and the environment. There were clear stoichiometric relationships between glucose, fructose and sucrose per flower, but DHA per flower was only weakly correlated with the amount of other sugars, suggesting that accumulation of the triose sugar is indirectly coupled to secretion of the larger sugars by the nectary parenchyma.

show abstract

“…Subsequent studies in Arabidopsis (Gibon et al, 2004b(Gibon et al, , 2006Mugford et al, 2014;Mengin et al, 2017) revealed that the primary event is a restriction of Suc consumption for growth in the light period and that the increase in allocation to starch is associated with a large increase of Glc and Fru. Hydrolysis of Suc to reducing sugars and their phosphorylation to hexose phosphates provides a mechanism to decrease net Suc synthesis and increase allocation to starch (Huber, 1989;Kingston-Smith et al, 1999;Macrae and Lunn, 2006;Stitt et al, 2010). This complex response is not explicitly addressed by the AD model, which focuses on starch degradation.…”

Section: Pacing Of Starch Mobilization To Dawn Does Not Require Modifmentioning

confidence: 99%

Response of the Circadian Clock and Diel Starch Turnover to One Day of Low Light or Low CO₂

et al. 2019

View full text Add to dashboard Cite

Diel starch turnover responds rapidly to changes in the light regime. We investigated if these responses require changes in the temporal dynamics of the circadian clock. Arabidopsis (Arabidopsis thaliana) was grown in a 12-h photoperiod for 19 d, shifted to three different reduced light levels or to low CO 2 for one light period, and returned to growth conditions. The treatments produced widespread changes in clock transcript abundance. However, almost all of the changes were restricted to extreme treatments that led to carbon starvation and were small compared to the magnitude of the circadian oscillation. Changes included repression of EARLY FLOWERNG 4, slower decay of dusk components, and a slight phase delay at the next dawn, possibly due to abrogated Evening Complex function and sustained expression of PHYTOCHROME INTERACTING FACTORs and REVEILLEs during the night. Mobilization of starch in the night occurred in a linear manner and was paced to dawn, both in moderate treatments that did not alter clock transcripts and in extreme treatments that led to severe carbon starvation. We conclude that pacing of starch mobilization to dawn does not require retrograde carbon signaling to the transcriptional clock. On the following day, growth decreased, sugars rose, and starch accumulation was stimulated in low-light-treated plants compared to controls. This adaptive response was marked after moderate treatments and occurred independently of changes in the transcriptional clock. It is probably a time-delayed response to low-C signaling in the preceding 24-h cycle, possibly including changes in PHYTOCHROME INTERACTING FACTOR and REVEILLE expression.

show abstract

Control of Sucrose Biosynthesis

Abstract: The sections in this article areIntroductionPathways of Sucrose Biosynthesis in LeavesControl of Sucrose Biosynthesis – The PrecursorsThe Committed Enzymes of Sucrose BiosynthesisIntegrated Pathway ControlFuture Perspectives

Cited by 7 publications

References 136 publications

Photosynthate partitioning to starch in Arabidopsis thaliana is insensitive to light intensity but sensitive to photoperiod due to a restriction on growth in the light in short photoperiods

Photosynthate partitioning to starch in Arabidopsis thaliana is insensitive to light intensity but sensitive to photoperiod due to a restriction on growth in the light in short photoperiods

Influence of genotype, floral stage, and water stress on floral nectar yield and composition of mānuka (Leptospermum scoparium)

Response of the Circadian Clock and Diel Starch Turnover to One Day of Low Light or Low CO₂

Contact Info

Product

Resources

About

Control of Sucrose Biosynthesis

Abstract: The sections in this article areIntroductionPathways of Sucrose Biosynthesis in LeavesControl of Sucrose Biosynthesis – The PrecursorsThe Committed Enzymes of Sucrose BiosynthesisIntegrated Pathway ControlFuture Perspectives

Cited by 7 publications

References 136 publications

Photosynthate partitioning to starch in Arabidopsis thaliana is insensitive to light intensity but sensitive to photoperiod due to a restriction on growth in the light in short photoperiods

Photosynthate partitioning to starch in Arabidopsis thaliana is insensitive to light intensity but sensitive to photoperiod due to a restriction on growth in the light in short photoperiods

Influence of genotype, floral stage, and water stress on floral nectar yield and composition of mānuka (Leptospermum scoparium)

Response of the Circadian Clock and Diel Starch Turnover to One Day of Low Light or Low CO2

Contact Info

Product

Resources

About

Response of the Circadian Clock and Diel Starch Turnover to One Day of Low Light or Low CO₂