NDLI: Increased levels of adenine nucleotides modify the interaction between starch synthesis and respiration when adenine is supplied to discs from growing potato tubers

Content Provider	Springer Nature Link
Author	Loef, Irene Stitt, Mark Geigenberger, Peter
Copyright Year	2001
Abstract	To investigate the importance of the overall size of the total adenine nucleotide pool for the regulation of primary metabolism in growing potato tubers, freshly cut discs were provided with zero or 2 mM adenine in the presence of 1 or 100 mM [U-14C]glucose or 100 mM [U-14C]sucrose in the presence and absence of 20 mM orthophosphate (Pi). Adenine led to a 150–250% increase of the total adenine nucleotide pool, which included an increase of ADP, a larger increase of ATP and an increase of the ATP:ADP ratio. There was a 50–100% increase of ADP-glucose (ADPGlc), and starch synthesis was stimulated. Respiratory oxygen uptake was stimulated, and the levels of glycerate-3-phosphate, phosphoenolpyruvate and α-ketoglutarate decreased. The response to adenine was not modified by Pi. It is proposed that increased ATP stimulates ADPGlc pyrophosphorylase, leading to a higher rate of starch synthesis. The impact on starch synthesis is constrained, however, because increased ADP can lead to a stimulation of respiration and decline of glycerate-3-phosphate, which will inhibit ADPGlc pyrophosphorylase. The quantitative impact depends on the conditions. In the presence of 1 mM glucose, the levels of phosphorylated intermediates and the rate of starch synthesis were low. Adenine led to a relatively large stimulation of respiration, but only a small stimulation of starch synthesis. In the presence of 100 mM glucose, discs contained high levels of phosphorylated intermediates, low ATP:ADP ratios (<3) and low rates of starch synthesis (<20% of the metabolised glucose). Adenine led to marked increase of ATP and 2- to 4-fold stimulation of starch synthesis. Discs incubated with 100 mM sucrose already had high ATP:ADP ratios (>8) and high rates of starch synthesis (>50% of the metabolised sucrose). Adenine led to a further increase, but the stimulation was less marked than in high glucose. These results have implications for the function of nucleotide cofactors in segregating sucrose mobilisation and respiration, and the need for energy conservation during sugar-starch conversions.
Starting Page	782
Ending Page	791
Page Count	10
File Format	PDF
ISSN	00320935
Journal	Planta
Volume Number	212
Issue Number	5
e-ISSN	14322048
Language	English
Publisher	Springer-Verlag
Publisher Date	2001-04-12
Publisher Place	Berlin/Heidelberg
Access Restriction	One Nation One Subscription (ONOS)
Content Type	Text
Resource Type	Article
Subject	Genetics Plant Science

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

Overexpression of pyrophosphatase leads to increased sucrose degradation and starch synthesis, increased activities of enzymes for sucrose-starch interconversions, and increased levels of nucleotides in growing potato tubers

Orotate leads to a specific increase in uridine nucleotide levels and a stimulation of sucrose degradation and starch synthesis in discs from growing potato tubers

The Sucrose Analog Palatinose Leads to a Stimulation of Sucrose Degradation and Starch Synthesis When Supplied to Discs of Growing Potato Tubers1

Regulation of sucrose to starch conversion in growing potato tubers

Contribution of adenosine 5′-diphosphoglucose pyrophosphorylase to the control of starch synthesis is decreased by water stress in growing potato tubers

Starch synthesis in transgenic potato tubers with increased 3-phosphoglyceric acid content as a consequence of increased 6-phosphofructokinase activity

The contribution of adenosine 5′-diphosphoglucose pyrophosphorylase to the control of starch synthesis in potato tubers

Metabolism in slices from growing potato tubers responds differently to addition of sucrose and glucose

Agrobacterial rol genes modify thermodynamic and structural properties of starch in microtubers of transgenic potato

Increased levels of adenine nucleotides modify the interaction between starch synthesis and respiration when adenine is supplied to discs from growing potato tubers

Similar Documents

Overexpression of pyrophosphatase leads to increased sucrose degradation and starch synthesis, increased activities of enzymes for sucrose-starch interconversions, and increased levels of nucleotides in growing potato tubers

Orotate leads to a specific increase in uridine nucleotide levels and a stimulation of sucrose degradation and starch synthesis in discs from growing potato tubers

The Sucrose Analog Palatinose Leads to a Stimulation of Sucrose Degradation and Starch Synthesis When Supplied to Discs of Growing Potato Tubers1

Regulation of sucrose to starch conversion in growing potato tubers

Contribution of adenosine 5′-diphosphoglucose pyrophosphorylase to the control of starch synthesis is decreased by water stress in growing potato tubers

Starch synthesis in transgenic potato tubers with increased 3-phosphoglyceric acid content as a consequence of increased 6-phosphofructokinase activity

The contribution of adenosine 5′-diphosphoglucose pyrophosphorylase to the control of starch synthesis in potato tubers

Metabolism in slices from growing potato tubers responds differently to addition of sucrose and glucose

Agrobacterial rol genes modify thermodynamic and structural properties of starch in microtubers of transgenic potato

Increased levels of adenine nucleotides modify the interaction between starch synthesis and respiration when adenine is supplied to discs from growing potato tubers