Author: Zhenhua Wang, Jianghua Chen, Lin Weng, Xin Li, Xianglin Cao, Xiaohe Hu, Da Luo, and Jun Yang
Transcription factors and phytohormones have been reported to play crucial roles to regulate leaf complexity among plant species. Using the compound-leafed species
Lotus japonicus, a model legume plant with five visible leaflets, we characterized four independent mutants with reduced leaf complexity,
proliferating floral meristem (pfm),
proliferating floral organ-2 (pfo-2),
fused leaflets1 (ful1) and
umbrella leaflets (uml), which were further identified as loss-of-function mutants of
Arabidopsis orthologs
LEAFY (
LFY),
UNUSUAL FLORAL ORGANS (
UFO),
CUP-SHAPED COTYLEDON 2 (
CUC2) and
PIN-FORMED 1 (
PIN1), respectively. Comparing the leaf development of wild-type and mutants by a scanning electron microscopy approach, leaflet initiation and/or dissection were found to be affected in these mutants. Expression and phenotype analysis indicated that
PFM/LjLFY and
PFO/LjUFO determined the basipetal leaflet initiation manner in
L. japonicus. Genetic analysis of
ful1 and
uml mutants and their double mutants revealed that the
CUC2-like gene and auxin pathway also participated in leaflet dissection in
L. japonicus, and their functions might influence cytokinin biogenesis directly or indirectly. Our results here suggest that multiple genes were interplayed and played conserved functions in controlling leaf complexity during compound leaf development in
L. japonicus.
Wang Z, Chen J, Weng L, Li X, Cao X, Hu X, Luo D, Yang J (2013) Multiple components are integrated to determine leaf complexity in Lotus japonicus. J. Integr. Plant Biol. 55(5), 419–433.