Cell wall invertase expression at the apical meristem alters floral, architectural, and reproductive traits in Arabidopsis thaliana

Abstract

SummaryResource allocation is a major determinant of plant ®tness and is in¯uenced by external as well as internal stimuli. We have investigated the effect of cell wall invertase activity on the transition from vegetative to reproductive growth, in¯orescence architecture, and reproductive output, i.e. seed production, in the model plant Arabidopsis thaliana by expressing a cell wall invertase under a meristem-speci®c promoter. Increased cell wall invertase activity causes accelerated¯owering and an increase in seed yield by nearly 30%. This increase is caused by an elevation of the number of siliques, which results from enhanced branching of the in¯orescence. On the contrary, as cytosolic enzyme, the invertase causes delayed¯ower-ing, reduced seed yield, and branching. This demonstrates that invertases not only are important in determining sink strength of storage organs but also play a role in regulating developmental processes.

Transitioning to the Next Phase: The Role of Sugar Signaling throughout the Plant Life Cycle

“…Meristem-specific overexpression of cell wall or cytosolic invertase in Arabidopsis changes the shoot branching pattern in a complex manner, differentially affecting the formation of axillary inflorescences, branching of the main inflorescence, and branching of side inflorescences (Heyer et al, 2004). This suggests that the Suc/hexose ratio in specific cellular compartments is critical for the branching pattern.…”

“…Plants overexpressing the Suc biosynthetic enzyme Suc-P synthase flowered earlier and produced more flowers (Micallef et al, 1995;Baxter et al, 2003). Meristemspecific expression of the Suc-hydrolyzing enzyme cell wall invertase also led to accelerated flowering and increased seed yield, whereas expression of cytosolic invertase had the opposite effect (Heyer et al, 2004). Mutants in starch synthesis and breakdown flower late (Corbesier et al, 1998), in addition to having an extended juvenile phase (Matsoukas et al, 2013).…”

The Silver Lining of a Viral Agent: Increasing Seed Yield and Harvest Index in Arabidopsis by Ectopic Expression of the Potato Leaf Roll Virus Movement Protein

“…It is well established that Suc has a stimulatory role on flowering induction at the shoot apical meristem in Arabidopsis and other plant species (Bernier et al, 1993;Corbesier et al, 1998;Roldan et al, 1999). Hence, changes in sink strength favoring assimilate supply, for instance by meristem-specific expression of yeast (Saccharomyces cerevisiae) cell wall invertase, caused accelerated flowering, whereas reduction in sink strength, mediated by transgenic expression of the invertase in the cytosol, delayed flowering (Heyer et al, 2004). In addition to this potentially direct effect of increased carbohydrate supply on flowering transition, increased assimilate allocation to the shoot apex might have indirectly stimulated phloemmediated trafficking of signaling molecules such as FLOWERING LOCUS transcription factor, which has recently been shown to act as long-distance protein signal for flowering induction in Arabidopsis (Corbesier et al, 2007).…”

Temporal Changes in Allocation and Partitioning of New Carbon as 11C Elicited by Simulated Herbivory Suggest that Roots Shape Aboveground Responses in Arabidopsis

“…In Arabidopsis, invertases are not only the main route of Suc metabolism but are essential for normal plant growth and development (Barratt et al, 2009). Invertases also play a crucial role in regulating the supply of photosynthate to naturally occurring sink tissues (Tang et al, 1999;Weschke et al, 2003;Heyer et al, 2004;Roitsch and González, 2004) and are known to be up-regulated during gall formation (Rehill and Schultz, 2003;Siemens et al, 2011) and after wounding and insect attack (Zhang et al, 1996;Ohyama et al, 1998;Rosenkranz et al, 2001;Arnold and Schultz, 2002).…”