Arabidopsis female gametophyte gene expression map reveals similarities between plant and animal gametes.
The development of multicellular organisms is controlled by differential gene expression whereby cells adopt distinct fates. A spatially resolved view of gene expression allows the elucidation of transcriptional networks that are linked to cellular identity and function. The haploid female gametophyte of flowering plants is a highly reduced organism: at maturity, it often consists of as few as three cell types derived from a common precursor [1, 2]. However, because of its inaccessibility and small size, we know little about the molecular basis of cell specification and differentiation in the female gametophyte. Here we report expression profiles of all cell types in the mature Arabidopsis female gametophyte. Differentially expressed posttranscriptional regulatory modules and metabolic pathways characterize the distinct cell types. Several transcription factor families are overrepresented in the female gametophyte in comparison to other plant tissues, e.g., type I MADS domain, RWP-RK, and reproductive meristem transcription factors. PAZ/Piwi-domain encoding genes are upregulated in the egg, indicating a role of epigenetic regulation through small RNA pathways-a feature paralleled in the germline of animals [3]. A comparison of human and Arabidopsis egg cells for enrichment of functional groups identified several similarities that may represent a consequence of coevolution or ancestral gametic features.
Institute of Plant Biology and Zürich-Basel Plant Science Center, University of Zürich, Zollikerstrasse 107, 8008 Zürich, Switzerland.
Samuel E
SE
Wuest
Kitty
K
Vijverberg
Anja
A
Schmidt
Manuel
M
Weiss
Jacqueline
J
Gheyselinck
Miriam
M
Lohr
Frank
F
Wellmer
Jörg
J
Rahnenführer
Christian
C
von Mering
Ueli
U
Grossniklaus
D000818:Animals; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D055993:Germ Cells, Plant / Q000378:metabolism*; D006801:Humans; D010063:Ovum / Q000378:metabolism; D030821:Plants, Genetically Modified; D013045:Species Specificity
D029681:Arabidopsis Proteins