Characterization of proteins secreted during maize microspore culture: arabinogalactan proteins (AGPs) stimulate embryo development.
To study molecules secreted from cultured plant cells that promote development, maize microspores were transferred into culture and the conditioned media were collected over time and analysed. Electrophoresis indicated that both non-glycosylated and glycosylated proteins including arabinogalactan proteins (AGPs) appeared in the medium and their concentration increased during the time of culture. The development of embryos was correlated with the presence of specific extracellular proteins, using an experimental system based on a tunicamycin inhibition test. In addition, a precise protein analysis was conducted using MALDI-TOF and ESI-MS-MS techniques. These approaches have allowed the identification of 5 other types of proteins: a cell wall invertase, two thaumatin isoforms, one 1-3 beta-glucanase and two chitinase isoforms. Altogether these experiments and results open ways for research aimed at understanding which molecules stimulate embryo formation. Moreover, AGPs may be used to stimulate the development of microspores (pollen embryogenesis) prepared from non-responsive genotypes.
Borderies
Gisèle
G
Centre de Biologie et de Physiologie végétales, UMR CNRS UPS 5546, Pôle de Biotechnologies Végétales, Université P. Sabatier, 24, Castanet-Tolosan, France.
le Béchec
Mickael
M
Rossignol
Michel
M
Lafitte
Claude
C
Le Deunff
Erwan
E
Beckert
Michel
M
Dumas
Christian
C
Elisabeth
Matthys-Rochon
MR
D017077:Culture Media, Conditioned; D005960:Glucosides; D009088:Mucoproteins / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D010696:Phloroglucinol / Q000031:analogs & derivatives*; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism*; D012639:Seeds / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*; D013194:Staining and Labeling; D046509:Tissue Culture Techniques; D003313:Zea mays / Q000196:embryology / Q000378:metabolism*
D017077:Culture Media, Conditioned; D005960:Glucosides; D009088:Mucoproteins; D010940:Plant Proteins; C104977:Yariv reagent; C006619:arabinogalactan proteins; D010696:Phloroglucinol