Genes normally expressed in the endosperm are expressed at early stages of microspore embryogenesis in maize.
Reproduction in flowering plants is characterized by double fertilization and the resulting formation of both the zygotic embryo and the associated endosperm. In many species it is possible to experimentally deviate pollen development towards an embryogenic pathway. This developmental switch, referred to as microspore embryogenesis or androgenesis, leads to the formation of embryos similar to zygotic embryos. In a screen for genes specifically expressed during early androgenesis, two maize genes were isolated by mRNA differential display. Both genes represent new molecular markers expressed at a very young stage of androgenic embryogenesis. When their expression pattern was studied during normal reproductive development, both showed early endosperm-specific expression. Investigation of the cytological features of young androgenic embryos revealed that they present a partially coenocytic organization similar to that of early endosperm. These findings suggest that maize androgenesis may possibly involve both embryogenesis and the establishment of endosperm-like components.
Magnard
J L
JL
Reproduction et Développement des Plantes, Ecole Normale Supérieure de Lyon, UMR 5667 CNRS-INRA-UCB Lyon, France.
Le Deunff
E
E
Domenech
J
J
Rogowsky
P M
PM
Testillano
P S
PS
Rougier
M
M
Risueño
M C
MC
Vergne
P
P
Dumas
C
C
D015139:Blotting, Southern; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics*; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011058:Pollen / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D012150:Polymorphism, Restriction Fragment Length; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012098:Reproduction / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012639:Seeds / Q000235:genetics* / Q000254:growth & development; D017422:Sequence Analysis, DNA; D003313:Zea mays / Q000235:genetics* / Q000254:growth & development
D018076:DNA, Complementary; D018744:DNA, Plant; D010940:Plant Proteins; D012333:RNA, Messenger