Genetic analysis as a tool to investigate the molecular mechanisms underlying seed development in maize.
BACKGROUND
In angiosperms the seed is the outcome of double fertilization, a process leading to the formation of the embryo and the endosperm. The development of the two seed compartments goes through three main phases: polarization, differentiation of the main tissues and organs and maturation.


METHODS
This review focuses on the maize kernel as a model system for developmental and genetic studies of seed development in angiosperms. An overview of what is known about the genetic and molecular aspects underlying embryo and endosperm formation and maturation is presented. The role played by embryonic meristems in laying down the plant architecture is discussed. The acquisition of the different endosperm domains are presented together with the use of molecular markers available for the detection of these domains. Finally the role of programmed cell death in embryo and endosperm development is considered.


CONCLUSIONS
The sequence of events occurring in the developing maize seed appears to be strictly regulated. Proper seed development requires the co-ordinated expression of embryo and endosperm genes and relies on the interaction between the two seed components and between the seed and the maternal tissues. Mutant analysis is instrumental in unravelling the genetic control underlying the formation of each compartment as well as the molecular signals interplaying between the two compartments.
Consonni
Gabriella
G
Dipartimento di Produzione Vegetale, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy. gabriella.consonni@unimi.it
Gavazzi
Giuseppe
G
Dolfini
Silvana
S
D017209:Apoptosis; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D012639:Seeds / Q000235:genetics* / Q000254:growth & development*; D003313:Zea mays / Q000196:embryology* / Q000235:genetics*