A choice between glycogen and delta-crystallin accumulation is made in glial cells and not influenced by overlying neurons.
Chick-embryo neuroretinal cells convert extensively into lens under low-glucose conditions, but this transdifferentiation process is blocked by high-glucose media. We have previously observed an inverse relationship between the levels of glycogen (a marker of normal retinoglial differentiation) and of delta-crystallin (a lens marker) in such cultures. However, most of the glycogen accumulated under high-glucose conditions is apparently localized in those glial (G) cells underlying clusters of neurons (N cells). We here show that glial-enriched cultures (largely depleted of N cells) both accumulate glycogen and fail to transdifferentiate in high-glucose media. Moreover, glycogen localization in groups of glial cells is unaffected by the absence of N cells. Thus the choice between normal and foreign differentiation pathways is made autonomously within the retinoglial-cell population and is not influenced significantly by the presence or absence of N cells.
Karim
S A
SA
Department of Biology, Faculty of Science, King Abdul Aziz University, Jeddah, Saudi Arabia.
de Pomerai
D I
DI
D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D002642:Chick Embryo; D003459:Crystallins / Q000378:metabolism*; D003470:Culture Media; D005947:Glucose; D006003:Glycogen / Q000378:metabolism*; D006651:Histocytochemistry; D009457:Neuroglia / Q000166:cytology / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D012160:Retina / Q000166:cytology / Q000378:metabolism*
D003459:Crystallins; D003470:Culture Media; D006003:Glycogen; D005947:Glucose