Identification of a potential structural marker for embryogenic competency in the Brassica napus spp. oleifera embryogenic tissue.
The Brassica napus secondary embryogenesis system requires no exogenous growth regulator to stimulate embryo development. It is stable embryogenically over a long period of culture and has a distinct pre-embryogenic stage. This system was used to investigate the morphological and cellular changes occurring in the embryogenic tissue compared to non-embryogenic tissue using various microscopy techniques. A unique ultrastructural feature designated the extracellular matrix (ECM) was observed on the surface of pre-embryogenic embryoids but not on the non-embryogenic individuals. The ECM layer was found to be dominant in the pre-embryogenic stage and reduced to fragments during embryo growth and development in mature embryogenic tissue. This is a novel aspect of the phenotype previously unreported in the Brassica system. This structure might be linked to acquisition of embryogenic competence.
Namasivayam
Parameswari
P
Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia. parameswari@putra.upm.edu.my
Skepper
Jeremy
J
Hanke
David
D
D015415:Biomarkers / Q000032:analysis; D029688:Brassica napus / Q000145:classification / Q000196:embryology* / Q000648:ultrastructure*; D005109:Extracellular Matrix / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D046509:Tissue Culture Techniques
D015415:Biomarkers