AtFLL2, a member of the FLO2 gene family, affects the enlargement of leaves at the vegetative stage and facilitates the regulation of carbon metabolism and flow

Arabidopsis thaliana FLL2, a member of the FLO2 gene family, is expressed specifically in green leaves. The fll2 mutant showed significantly large rosette leaves and reduced the chlorophyll content. The sucrose content was significantly reduced. The glucose content was higher during the vegetative growth stage but decreased during the early reproductive growth stage. The amount of assimilated starch was lower than that in the wild type plant. The expression levels of genes involved in biosynthesis of sucrose and starch were largely altered. These results suggest that, in the fll2 mutant, a small amount of photosynthetic products was used for the biosynthesis of starch, and the products were supplied to promote intracellular growth of the source organs or for transport to the sink organs. These findings suggest that FLL2 is a factor affecting the expression level of genes involved in sugar metabolism, whose mutation caused a change in the assimilated products. Abbreviations : DAS: days after sowing Arabidopsis thaliana FLL2 affects to the sugar metabolism and flow, causing enlarged rosette leaves and reduced chlorophyll content.拟南芥（Arabidopsis thaliana）FLL2属于FLO2基因家族成员，特异地在绿色叶片中表达。fll2突变体的莲座叶显著增大，叶绿素含量降低，蔗糖含量显著下降。营养生长阶段的葡萄糖含量更高，但在生殖生长早期出现下降。该突变体的同化淀粉积累量低于野生型植株。参与蔗糖与淀粉生物合成的基因的表达水平发生了显著改变。上述结果表明，在fll2突变体中，少量光合产物被用于淀粉的生物合成，这些产物或用于促进源器官的细胞内生长，或被转运至库器官。本研究发现显示，FLL2是调控糖代谢相关基因表达水平的因子，其突变会引发同化产物的代谢变化。缩写：DAS：播种后天数（days after sowing）。拟南芥FLL2可影响糖代谢与糖转运过程，导致莲座叶膨大及叶绿素含量降低。