AtLSG1-2 Regulates Leaf Growth by Affecting Cell Proliferation and the Onset of Endoreduplication and Synergistically Interacts with AtNMD3 during Cell Proliferation Process.
AtLSG1-2 is a circularly permuted GTPase required for ribosome biogenesis and recently shown to be involved in early leaf development, although it was unclear how AtLSG1-2 affects leaf growth. Here, we found thatatlsg1-2mutants had reduced leaf size as a result of decreased cell size and cell number. Leaf kinematic analysis and CYCB1;1::GUS expression pattern inatlsg1-2mutant indicated that loss of function ofAtLSG1-2delays the transition from cell division to cell expansion. Decreases in ploidy levels and trichome branch number suggest that AtLSG1-2 deficiency suppresses endoreduplication. Real-time PCR analysis showed that genes specifically expressed in the proliferation stage were highly expressed and those involved in endoreduplication were differentially regulated. LSG1 is known to mediate the recruitment of nucleocytoplasmic shuttling protein NMD3 back to the nucleus in yeast, yet their relationship was unclear in plants. Our genetic analysis revealed that theatlsg1 atnmd3double mutant displayed enhanced phenotypes as compared with the respective single mutant and that AtLSG1-2 and AtNMD3 synergistically affect the cell proliferation process.
Applied Biotechnology Center, Wuhan Institute of BioengineeringWuhan, China; Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and TechnologyThuwal, Saudi Arabia.
Huayan
H
Zhao
Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences Wuhan, China.
Shiyou
S
Lü
Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and TechnologyThuwal, Saudi Arabia; Department of Horticulture Sciences, Texas A&M University, College StationTX, USA; Texas A&M Agrilife Research Center, DallasTX, USA.
Liming
L
Xiong
AtLSG1-2; AtNMD3; cell division; endoreduplication; leaf growth