Cell Cycle modules in plants for entry into proliferation and for mitosis

Abstract

Cell cycle is an orderly progression through a series of events culminating in the duplication of chromosomes during S-phase and in the segregation of chromosomes into daughter cells during mitosis. The S-and M-phases are the so called active phases which are preceded by preparatory phases, called gap phases, when regulatory inputs are pereceived; G1 and G2, respectively (Fig. 6.1). Chromosomes during G1-, S and G2-phases (interphase) are decondensed within the nuclei but intephase chromosomes are still known to occupy distinct territories within the nuclei and this organisation is important for replication, transcription, repair and recombination processes (Schubert and Shaw 2011). Mitosis is a cell cycle period packed with morphological events subdivided into pro-, meta-, ana- and telophases followed by cytokinesis. Within this chapter we will focus on the central regulators of the cell cycle phase transitions, but before we get onto the regulators in large details we first summarise what are being regulated during these cell cycle phases with an aim to pinpoint conserved and plant specific mechanisms.