Involvement of five catalytically active Arabidopsis β‐amylases in leaf starch metabolism and plant growth

Monroe, Jonathan D.

doi:10.1002/pld3.199

Cited by 24 publications

(17 citation statements)

References 51 publications

(90 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In Arabidopsis leaves, β-amylases (BAMs, EC 3.2.1.2) control a significant part of starch degradation to maltose [ 265 ] ( Figure 5 ). The extractible activity of these enzymes is considered to be fairly stable, but different BAMs display dissimilar biochemical properties and are differently regulated by stress [ 265 , 266 ]. In particular, the activity of BAM3, which is primarily involved in night starch degradation in mesophyll cells, is decreased by cold stress [ 266 , 267 ].…”

Section: Protein S -Glutathionylation: Roles Of Glutathione In the Protection And Regulation Of Protein Functions Undementioning

confidence: 99%

Glutathione Metabolism in Plants under Stress: Beyond Reactive Oxygen Species Detoxification

2021

View full text Add to dashboard Cite

Glutathione is an essential metabolite for plant life best known for its role in the control of reactive oxygen species (ROS). Glutathione is also involved in the detoxification of methylglyoxal (MG) which, much like ROS, is produced at low levels by aerobic metabolism under normal conditions. While several physiological processes depend on ROS and MG, a variety of stresses can dramatically increase their concentration leading to potentially deleterious effects. In this review, we examine the structure and the stress regulation of the pathways involved in glutathione synthesis and degradation. We provide a synthesis of the current knowledge on the glutathione-dependent glyoxalase pathway responsible for MG detoxification. We present recent developments on the organization of the glyoxalase pathway in which alternative splicing generate a number of isoforms targeted to various subcellular compartments. Stress regulation of enzymes involved in MG detoxification occurs at multiple levels. A growing number of studies show that oxidative stress promotes the covalent modification of proteins by glutathione. This post-translational modification is called S-glutathionylation. It affects the function of several target proteins and is relevant to stress adaptation. We address this regulatory function in an analysis of the enzymes and pathways targeted by S-glutathionylation.

show abstract

Section: Protein S -Glutathionylation: Roles Of Glutathione In the Protection And Regulation Of Protein Functions Undementioning

confidence: 99%

Glutathione Metabolism in Plants under Stress: Beyond Reactive Oxygen Species Detoxification

2021

View full text Add to dashboard Cite

show abstract

“…The rhythmic control of MIPS1 abundance is consistent with anticipation of light-induced oxidative stress, providing a potential physiological function in addition to the subsequent, light-responsive induction of myoinositol production. BAM3 (Figure 2B) is the dominant beta-amylase contributing to starch degradation (61). The circadian clock is key for the timing of night-time starch degradation (62).…”

Section: Proteins With Rhythmic Abundancementioning

confidence: 99%

The circadian clock gene circuit controls protein and phosphoprotein rhythms inArabidopsis thaliana

Krahmer

Hindle

Perby

et al. 2019

Preprint

View full text Add to dashboard Cite

The 24-hour rhythmicity in the levels of many eukaryotic mRNAs contrasts with the long half-lives of most detected proteins. Such stable molecular species are not expected to reflect the RNA rhythms, emphasizing the need to test the circadian regulation of protein abundance and modification. Here we present circadian proteomic and comparable phosphoproteomic time-series from Arabidopsis thaliana plants, estimating that 0.4% of quantified proteins and a much larger proportion of quantified phosphosites were rhythmic under constant light conditions. Approximately half of the quantified phospho-sites were most phosphorylated at subjective dawn, when SnRK1 protein kinase was a candidate regulator.A CCA1-over-expressing line that disables the plant clock gene circuit lacked most or all circadian protein phosphorylation, indicating that the phospho-dawn is regulated by the canonical clock mechanism. The few phospho-sites that fluctuated despite CCA1-over-expression still tended to peak in abundance close to subjective dawn, indicating that their temporal regulation was less dependent on the clock gene circuit. To test the potential functional relevance of our datasets, we conduct phosphomimetic experiments using the bifunctional enzyme fructose-6-phosphate-2-kinase / phosphatase (F2KP), as an example. The clock gene circuit controls diverse protein targets in metabolism and physiology via phosphorylation, including where the bulk abundance of the cognate proteins is arrhythmic.

show abstract

“…BAM3 ( Fig. 2 B ) is the dominant beta-amylase contributing to starch degradation ( 60 ). The circadian clock is key for the timing of night-time starch degradation ( 61 ).…”

Section: Discussionmentioning

confidence: 99%

The Circadian Clock Gene Circuit Controls Protein and Phosphoprotein Rhythms in Arabidopsis thaliana

Krahmer

Hindle

Perby

et al. 2022

Molecular & Cellular Proteomics

View full text Add to dashboard Cite

Twenty-four-hour, circadian rhythms control many eukaryotic mRNA levels, whereas the levels of their more stable proteins are not expected to reflect the RNA rhythms, emphasizing the need to test the circadian regulation of protein abundance and modification. Here we present circadian proteomic and phosphoproteomic time series from Arabidopsis thaliana plants under constant light conditions, estimating that just 0.4% of quantified proteins but a much larger proportion of quantified phospho-sites were rhythmic. Approximately half of the rhythmic phospho-sites were most phosphorylated at subjective dawn, a pattern we term the “phospho-dawn.” Members of the SnRK/CDPK family of protein kinases are candidate regulators. A CCA1 -overexpressing line that disables the clock gene circuit lacked most circadian protein phosphorylation. However, the few phospho-sites that fluctuated despite CCA1 -overexpression still tended to peak in abundance close to subjective dawn, suggesting that the canonical clock mechanism is necessary for most but perhaps not all protein phosphorylation rhythms. To test the potential functional relevance of our datasets, we conducted phosphomimetic experiments using the bifunctional enzyme fructose-6-phosphate-2-kinase/phosphatase (F2KP), as an example. The rhythmic phosphorylation of diverse protein targets is controlled by the clock gene circuit, implicating posttranslational mechanisms in the transmission of circadian timing information in plants.

show abstract

Involvement of five catalytically active Arabidopsis β‐amylases in leaf starch metabolism and plant growth

Cited by 24 publications

References 51 publications

Glutathione Metabolism in Plants under Stress: Beyond Reactive Oxygen Species Detoxification

Glutathione Metabolism in Plants under Stress: Beyond Reactive Oxygen Species Detoxification

The circadian clock gene circuit controls protein and phosphoprotein rhythms inArabidopsis thaliana

The Circadian Clock Gene Circuit Controls Protein and Phosphoprotein Rhythms in Arabidopsis thaliana

Contact Info

Product

Resources

About