Abstract
Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase. Using affinity chromatography on agarose-5-(4-aminophenyl-phosphoryl) uridine 3'(2') monophosphate as a powerful and final enrichment step, the enzyme was purified to homogeneity and characterized as ribonuclease I (RNase I) according to the following data: (a) it has an M(r) of 22,000 (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), a pH-optimum of pH 5.5, a pl of 3.9, and its activity was found to be insensitive to EDTA; (b) the enzyme splits single-stranded RNA endonucleolytically by a phosphotransferase reaction yielding 2',3'-cNMPs as primary monomeric products; (c) as studied with diribonucleoside monophosphates as substrates, the enzyme exhibits a pronounced preference for 5' purine residues adjacent to the cleavage site. Most interestingly, in vivo synthesis and secretion was found to be induced when tomato cells were specifically starved for phosphate as mineral nutrient. (a) Extracellular enzyme activity increased about tenfold after transfer of phosphate-grown cells into medium lacking only phosphate. Accordingly, this increase in activity was not detectable when cells were constantly supplied with phosphate. (b) Biosynthetically labeling of the extracellular protein with radioactive amino acids was detectable by sodium dodecyl sulfate-polyacrylamide gel electrophoresis/fluorography directly within the bulk of extracellular proteins. Therefore, we propose that the secreted tomato RNase I synthesized upon phosphate starvation is a component of a higher plant inducible rescue system for scavenging exogenous phosphate.
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Claims 10
Claim · model-written summary
Tomato cell cultures began secreting RNA degrading activity during transition to stationary growth.
- Taxon
- tomato
Solanum lycopersicume0 - Organ / stage
- cellse0
- Outcome
- secrete an RNA-degrading enzyme activitye0
- Qualifier
- transition from logarithmic to stationary growth phasee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
Claim · model-written summary
Tomato RNase I had M(r) of 22,000.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- ribonuclease I (RNase I)e1
- Outcome
- M(r)e1
- Value
- 22,000e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
e1“the enzyme was purified to homogeneity and characterized as ribonuclease I (RNase I) according to the following data: (a) it has an M(r) of 22,000 (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), a pH-optimum of pH 5.5, a pl of 3.9, and its activity was found to be insensitive to EDTA”
Claim · model-written summary
Tomato RNase I had pH-optimum of pH 5.5.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- ribonuclease I (RNase I)e1
- Outcome
- pH-optimume1
- Value
- pH 5.5e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
e1“the enzyme was purified to homogeneity and characterized as ribonuclease I (RNase I) according to the following data: (a) it has an M(r) of 22,000 (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), a pH-optimum of pH 5.5, a pl of 3.9, and its activity was found to be insensitive to EDTA”
Claim · model-written summary
Tomato RNase I had pl of 3.9.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- ribonuclease I (RNase I)e1
- Outcome
- ple1
- Value
- 3.9e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
e1“the enzyme was purified to homogeneity and characterized as ribonuclease I (RNase I) according to the following data: (a) it has an M(r) of 22,000 (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), a pH-optimum of pH 5.5, a pl of 3.9, and its activity was found to be insensitive to EDTA”
Claim · model-written summary
Tomato RNase I insensitive to EDTA.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- ribonuclease I (RNase I)e1
- Outcome
- insensitive to EDTAe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
e1“the enzyme was purified to homogeneity and characterized as ribonuclease I (RNase I) according to the following data: (a) it has an M(r) of 22,000 (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), a pH-optimum of pH 5.5, a pl of 3.9, and its activity was found to be insensitive to EDTA”
Claim · model-written summary
Tomato RNase I splits single-stranded RNA endonucleolytically.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- ribonuclease I (RNase I)e2
- Outcome
- splits single-stranded RNA endonucleolyticallye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
e1“the enzyme splits single-stranded RNA endonucleolytically by a phosphotransferase reaction yielding 2',3'-cNMPs as primary monomeric products”
e2“the enzyme was purified to homogeneity and characterized as ribonuclease I (RNase I) according to the following data: (a) it has an M(r) of 22,000 (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), a pH-optimum of pH 5.5, a pl of 3.9, and its activity was found to be insensitive to EDTA”
Claim · model-written summary
Tomato RNase I preference for 5' purine residues.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- ribonuclease I (RNase I)e2
- Outcome
- preference for 5' purine residuese1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
e1“the enzyme exhibits a pronounced preference for 5' purine residues adjacent to the cleavage site.”
e2“the enzyme was purified to homogeneity and characterized as ribonuclease I (RNase I) according to the following data: (a) it has an M(r) of 22,000 (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), a pH-optimum of pH 5.5, a pl of 3.9, and its activity was found to be insensitive to EDTA”
Claim · model-written summary
Phosphate starvation raised extracellular enzyme activity about tenfold.
- Taxon
- tomatoSolanum lycopersicume0
- Treatment
- medium lacking only phosphatee1
- Outcome
- Extracellular enzyme activitye1
- Direction
- increasede1
- Value
- about tenfolde1
- Comparator
- phosphate-grown cellse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
e1“Extracellular enzyme activity increased about tenfold after transfer of phosphate-grown cells into medium lacking only phosphate.”
Claim · model-written summary
Constant phosphate supply prevented the increase in extracellular enzyme activity.
- Taxon
- tomatoSolanum lycopersicume0
- Treatment
- constantly supplied with phosphatee1
- Outcome
- increase in activity was not detectablee1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
e1“Accordingly, this increase in activity was not detectable when cells were constantly supplied with phosphate.”
Claim · model-written summary
Newly synthesized extracellular protein was detectable by radioactive amino acid labeling.
- Taxon
- tomatoSolanum lycopersicume0
- Outcome
- extracellular protein with radioactive amino acids was detectablee1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Suspension-cultured cells of tomato (Lycopersicon esculentum) start to secrete an RNA-degrading enzyme activity during transition from logarithmic to stationary growth phase.”
e1“Biosynthetically labeling of the extracellular protein with radioactive amino acids was detectable by sodium dodecyl sulfate-polyacrylamide gel electrophoresis/fluorography directly within the bulk of extracellular proteins.”
The same questions in other papers
phosphorus · soil: biology · Solanum lycopersicum (tomato)Positive and negative results
2 papers in the same direction as this paper · 5 in the opposite direction
This paper is about lacking the nutrient, so it counts the other way round here.
- positive
- positive
- positive
4 papers more in this group
See all 8 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.