scholarly journals Blocking plasmodesmata in specific phloem cell types reduces axillary bud growth in Arabidopsis thaliana

2020 ◽  
Author(s):  
Andrea Paterlini ◽  
Delfi Dorussen ◽  
Franziska Fichtner ◽  
Martin van Rongen ◽  
Ruth Delacruz ◽  
...  

AbstractThe plasticity of above ground plant architecture depends on the regulated re-activation and growth of axillary meristems laid down in the axils of leaves along the stem, which often arrest as dormant buds. Plasmodesmata connecting plant cells might control the movement of regulators involved in this developmental switch. Constructs capable of occluding these structures were employed in phloem cell types, because of the importance of phloem in local and systemic trafficking. We show that over-accumulation of callose within companion cells of the Arabidopsis inflorescence reduces the growth rates of activated buds, but does not affect bud activation. Growth rate reductions were not dependent on the phloem-mobile strigolactone receptor, which regulates bud activation. Furthermore, there was no correlation with early bud sugar profiles, which can also affect bud activity and depend on phloem-mediated delivery. It is therefore possible that an as yet unknown mobile signal is involved in modulating branch growth rate.

2021 ◽  
Author(s):  
Andrea Paterlini ◽  
Delfi Dorussen ◽  
Franziska Fichtner ◽  
Martin Rongen ◽  
Ruth Delacruz ◽  
...  

2020 ◽  
Author(s):  
Rongna Wang ◽  
Junjie Qian ◽  
Zhongming Fang ◽  
Jihua Tang

Abstract Background: N is an important macronutrient required for plant development and significantly influences axillary bud outgrowth, which affects tillering and grain yields of rice. However, how different N concentrations affect axillary bud growth at the molecular and transcriptional levels remains unclear. Results: In this study, morphological changes in the axillary bud growth of rice seedlings under different N concentrations ranging from low to high levels were systematically observed. To investigate the expression of N-induced genes involved in axillary bud growth, we used RNA-seq technology to generate mRNA transcriptomic data from two tissue types, basal parts and axillary buds, of plants grown under six different N concentrations. In total, 10,221 and 12,180 DEGs induced by LN or HN supplies were identified in the basal parts and axillary buds, respectively, via comparisons to expression levels under NN level. Analysis of the coexpression modules from the DEGs of the basal parts and axillary buds revealed an abundance of related biological processes underlying the axillary bud growth of plants under N treatments. Among these processes, the activity of cell division and expansion was positively correlated with the growth rate of axillary buds of plants grown under different N supplies. Additionally, TFs and phytohormones were shown to play crucial roles in determining the axillary bud growth of plants grown under different N concentrations. Further validation of OsGS1;2 and OsGS2 , the rice mutants of which presented altered tiller numbers, validated our transcriptomic data. Conclusion: These results indicate that different N concentrations affect the axillary bud growth rate, and our study revealed comprehensive expression profiles of genes that respond to different N concentrations, providing an important resource for future studies attempting to determine how axillary bud growth is controlled by different N supplies.


2019 ◽  
Author(s):  
Rongna Wang ◽  
Junjie Qian ◽  
Zhongming Fang ◽  
Jihua Tang

Abstract Background: N is an important macronutrient required for plant development and significantly influences axillary bud outgrowth, which affects tillering and grain yields of rice. However, how different N concentrations affect axillary bud growth at the molecular and transcriptional levels remains unclear. Results: In this study, morphological changes in the axillary bud growth of rice seedlings under different N concentrations ranging from low to high levels were systematically observed. To investigate the expression of N-induced genes involved in axillary bud growth, we used RNA-seq technology to generate mRNA transcriptomic data from two tissue types, basal parts and axillary buds, of plants grown under six different N concentrations. In total, 10,221 and 12,180 DEGs induced by LN or HN supplies were identified in the basal parts and axillary buds, respectively, via comparisons to expression levels under NN level. Analysis of the coexpression modules from the DEGs of the basal parts and axillary buds revealed an abundance of related biological processes underlying the axillary bud growth of plants under N treatments. Among these processes, the activity of cell division and expansion was positively correlated with the growth rate of axillary buds of plants grown under different N supplies. Additionally, TFs and phytohormones were shown to play crucial roles in determining the axillary bud growth of plants grown under different N concentrations. Further validation of OsGS1;2 and OsGS2 , the rice mutants of which presented altered tiller numbers, validated our transcriptomic data. Conclusion: These results indicate that different N concentrations affect the axillary bud growth rate, and our study revealed comprehensive expression profiles of genes that respond to different N concentrations, providing an important resource for future studies attempting to determine how axillary bud growth is controlled by different N supplies.


2020 ◽  
Author(s):  
Rongna Wang ◽  
Junjie Qian ◽  
Zhongming Fang ◽  
Jihua Tang

Abstract Background: N is an important macronutrient required for plant development and significantly influences axillary bud outgrowth, which affects tillering and grain yields of rice. However, how different N concentrations affect axillary bud growth at the molecular and transcriptional levels remains unclear. Results: In this study, morphological changes in the axillary bud growth of rice seedlings under different N concentrations ranging from low to high levels were systematically observed. To investigate the expression of N-induced genes involved in axillary bud growth, we used RNA-seq technology to generate mRNA transcriptomic data from two tissue types, basal parts and axillary buds, of plants grown under six different N concentrations. In total, 10,221 and 12,180 DEGs induced by LN or HN supplies were identified in the basal parts and axillary buds, respectively, via comparisons to expression levels under NN level. Analysis of the coexpression modules from the DEGs of the basal parts and axillary buds revealed an abundance of related biological processes underlying the axillary bud growth of plants under N treatments. Among these processes, the activity of cell division and expansion was positively correlated with the growth rate of axillary buds of plants grown under different N supplies. Additionally, TFs and phytohormones were shown to play crucial roles in determining the axillary bud growth of plants grown under different N concentrations. Further validation of OsGS1;2 and OsGS2 , the rice mutants of which presented altered tiller numbers, validated our transcriptomic data. Conclusion: These results indicate that different N concentrations affect the axillary bud growth rate, and our study revealed comprehensive expression profiles of genes that respond to different N concentrations, providing an important resource for future studies attempting to determine how axillary bud growth is controlled by different N supplies.


2020 ◽  
Author(s):  
Rongna Wang ◽  
Junjie Qian ◽  
Zhongming Fang ◽  
Jihua Tang

Abstract Background: N is an important macronutrient required for plant development and significantly influences axillary bud outgrowth, which affects tillering and grain yields of rice. However, how different N concentrations affect axillary bud growth at the molecular and transcriptional levels remains unclear. Results: In this study, morphological changes in the axillary bud growth of rice seedlings under different N concentrations ranging from low to high levels were systematically observed. To investigate the expression of N-induced genes involved in axillary bud growth, we used RNA-seq technology to generate mRNA transcriptomic data from two tissue types, basal parts and axillary buds, of plants grown under six different N concentrations. In total, 10,221 and 12,180 DEGs induced by LN or HN supplies were identified in the basal parts and axillary buds, respectively, via comparisons to expression levels under NN level. Analysis of the coexpression modules from the DEGs of the basal parts and axillary buds revealed an abundance of related biological processes underlying the axillary bud growth of plants under N treatments. Among these processes, the activity of cell division and expansion was positively correlated with the growth rate of axillary buds of plants grown under different N supplies. Additionally, TFs and phytohormones were shown to play crucial roles in determining the axillary bud growth of plants grown under different N concentrations. Further validation of OsGS1;2 and OsGS2 , the rice mutants of which presented altered tiller numbers, validated our transcriptomic data. Conclusion: These results indicate that different N concentrations affect the axillary bud growth rate, and our study revealed comprehensive expression profiles of genes that respond to different N concentrations, providing an important resource for future studies attempting to determine how axillary bud growth is controlled by different N supplies.


2012 ◽  
Vol 5 (2) ◽  
pp. 173-182 ◽  
Author(s):  
Brian P. O’Neill ◽  
Matthew P. Purnell ◽  
David J. Anderson ◽  
Lars K. Nielsen ◽  
Stevens M. Brumbley

1998 ◽  
Vol 42 (8) ◽  
pp. 1900-1905 ◽  
Author(s):  
George S. Baillie ◽  
L. Julia Douglas

ABSTRACT A perfused biofilm fermentor, which allows growth-rate control of adherent microbial populations, was used to assess whether the susceptibility of Candida albicans biofilms to antifungal agents is dependent on growth rate. Biofilms were generated under conditions of glucose limitation and were perfused with drugs at a high concentration (20 times the MIC). Amphotericin B produced a greater reduction in the number of daughter cells in biofilm eluates than ketoconazole, fluconazole, or flucytosine. Similar decreases in daughter cell counts were observed when biofilms growing at three different rates were perfused with amphotericin B. In a separate series of experiments, intact biofilms, resuspended biofilm cells, and newly formed daughter cells were removed from the fermentor and were exposed to a lower concentration of amphotericin B for 1 h. The susceptibility profiles over a range of growth rates were then compared with those obtained for planktonic cells grown at the same rates under glucose limitation in a chemostat. Intact biofilms were resistant to amphotericin B at all growth rates tested, whereas planktonic cells were resistant only at low growth rates (≤0.13 h−1). Cells resuspended from biofilms were less resistant than intact biofilm populations but more resistant than daughter cells; the susceptibilities of both these cell types were largely independent of growth rate. Our findings indicate that the amphotericin B resistance of C. albicans biofilms is not simply due to a low growth rate but depends on some other feature of the biofilm mode of growth.


Sign in / Sign up

Export Citation Format

Share Document