The cell-cycle interactome: a source of growth regulators?

Area of Science:

• Plant biology
• Molecular genetics
• Developmental biology

Background:

• Leaf development requires precise control of cell proliferation and expansion for determinate organ size.
• Cell-cycle regulation is critical for leaf growth, involving a complex interactome of proteins controlling cell-cycle transitions.

Purpose of the Study:

• To review cell-cycle regulators impacting final leaf size when their expression is altered.
• To analyze mutants affecting cell-cycle proteins and their interaction networks in Arabidopsis.

Main Methods:

• Review of existing literature on cell-cycle regulators and their mutants.
• Phenotypic analysis of gain- and loss-of-function mutants for 27 genes interacting with cell-cycle proteins.
• Meta-analysis of cell-cycle interactome in relation to leaf growth.

Main Results:

• Mis-expression of cell-cycle-related genes frequently alters leaf growth.
• Three key trends regulate final organ size: cellular compensation, gene dosage, and proper ANAPHASE PROMOTING COMPLEX/CYCLOSOME (APC/C) activation for G2/M transition.
• The cell-cycle interactome is rich in leaf growth regulators.

Conclusions:

• The cell-cycle interactome plays a significant role in regulating final leaf size.
• Potential exists to identify novel leaf growth regulators within the cell-cycle regulatory network.