Esr proteins are secreted by the cells of the embryo surrounding region.

@article{Bonello2002EsrPA,
  title={Esr proteins are secreted by the cells of the embryo surrounding region.},
  author={J F Bonello and Sandrine Sevilla-Lecoq and Annick Berne and Mar{\'i}a Del Carmen Risue{\~n}o and Christian Dumas and Peter M Rogowsky},
  journal={Journal of experimental botany},
  year={2002},
  volume={53 374},
  pages={1559-68}
}
Three highly homologous Esr genes are expressed specifically in the embryo surrounding region at the micropylar end of the maize endosperm. The proteins belong to a family of small hydrophilic proteins that share a conserved motive with Clv3, the ligand of the receptor-like kinase Clv1. In this study, co-localization of Esr proteins with their mRNAs in the embryo surrounding region was shown with polyclonal antibodies recognizing all three Esr proteins. On a subcellular level the secretion of… CONTINUE READING