Meristem Maintenance in Arabidopsis thaliana

The shoot apical meristem (SAM) is the composition that patterns the airborne architecture of the plant, by producing lateral organs during development. In the model plant Arabidopsis thaliana, the SAM is definitely familiar like a characteristic dome, whether it’s located in the centre of a rosette of leaves or at the tip of an inflorescence. When senescence occurs and organogenesis ceases, the now inactive SAM still retains its characteristic appearance and it is never absorbed into a terminal structure, for instance a flower. Mutant plants that undergo termination represent a precious tool to realize how the SAM structure and operate are managed during plant existence.The goal of the work was to investigate the dynamics of meristem development through morphological and inherited studies of three Arabidopsis mutants which display unique modes of SAM termination: distorted architecture 1 (dar1), adenosine kinase 1 (adk1) and terminal flower 2 (tfl2)…

Contents: Meristem Maintenance in Arabidopsis thaliana

SUMMARY
DET APIKALA SKOTT MERISTEMET HOS ARABIDOPSIS THALIANA
INTRODUCTIO
ARABIDOPSIS THALIANA, PROBABLY THE MOST FAMOUS WEED IN THE
WORLD
ARABIDOPSIS SHOOT APICAL MERISTEM (SAM): STRUCTURE AND FUNCTION
Structure of the SAM
Coordination of cell proliferation and cell fate decisions
The role of plant growth regulators in SAM development
MERISTEM IDENTITY THROUGHOUT DEVELOPMENT: VEGETATIVE AND
REPRODUCTIVE PHAS
Vegetative phase
Reproductive phase
The transition to flowering
Floral development
LIGHT PERCEPTION AND SIGNALLING IN ARABIDOPSI
The photoreceptors and their downstream signalling pathways
The role of photoreceptors in Arabidopsis development
AIM OF THE WORK
RESULTS AND DISCUSSION
TERMINATION BY MERISTEM CONSUMPTION: THE dar1 MUTANT (I)
dar1 affects multiple aspects of plant development
dar1 affects SAM and RAM morphology
dar1 showed genetic interaction with known meristem mutants
DAR1 mapping by positional cloning
TERMINATION BY MERISTEM ARREST: adk1 MUTANT AND CYTOKININ
ACTION (II)
Cytokinin syndrome and meristem distortion in adk1 plants
adk1 meristem defect is due to overproliferation
The T-DNA is inserted in the ADK1 gene
Altered hormone sensitivity and cytokinin levels in adk1
TERMINATION BY LOSS OF MERISTEM IDENTITY: tfl2 MUTANT AND
GENE REPRESSION (III)
Cloning, characterisation and expression pattern of TFL2
TFL2 regulates plant development through gene repression
TFL2 is involved in both the photoperiod sensitive and the autonomous pathway of flowering
TFL2 AND THE MODULATION OF LIGHT SIGNALLING (VI)
TFL2 plays a role as a repressor in the modulation of light signalling…