Loading...
Please wait, while we are loading the content...
Similar Documents
Decrease in phosphoribulokinase activity by antisense RNA in transgenic tobacco. Relationship between photosynthesis, growth, and allocation at different nitrogen levels
| Content Provider | Semantic Scholar |
|---|---|
| Author | Banks Driscoll Parry Lawlor Knight Gray Paul |
| Copyright Year | 1999 |
| Abstract | To study the direct effects of photosynthesis on allocation of biomass by altering photosynthesis without altering leaf N or nitrate content, phosphoribulokinase (PRK) activity was decreased in transgenic tobacco (Nicotiana tabacum L.) with an inverted tobacco PRK cDNA and plants were grown at different N levels (0.4 and 5 mM NH4NO3). The activation state of PRK increased as the amount of enzyme was decreased genetically at both levels of N. At high N a 94% decrease in PRK activity had only a small effect (20%) on photosynthesis and growth. At low N a 94% decrease in PRK activity had a greater effect on leaf photosynthesis (decreased by up to 50%) and whole-plant photosynthesis (decreased by up to 35%) than at high N. These plants were up to 35% smaller than plants with higher PRK activities because they had less structural dry matter and less starch, which was decreased by 3- to 4-fold, but still accumulated to 24% to 31% of dry weight; young leaves contained more starch than older leaves in older plants. Leaves had a higher ion and water content, and specific leaf area was higher, but allocation between shoot and root was unaltered. In conclusion, low N in addition to a 94% decrease in PRK by antisense reduces the activity of PRK sufficient to diminish photosynthesis, which limits biomass production under conditions normally considered sink limited. |
| File Format | PDF HTM / HTML |
| DOI | 10.1104/pp.119.3.1125 |
| Alternate Webpage(s) | http://www.plantphysiol.org/content/plantphysiol/119/3/1125.full.pdf |
| PubMed reference number | 10069852 |
| Alternate Webpage(s) | https://doi.org/10.1104/pp.119.3.1125 |
| Journal | Medline |
| Volume Number | 119 |
| Issue Number | 3 |
| Journal | Plant physiology |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
