Cultured oligodendrocytes. A role for cell-substratum interaction in phenotypic expression

Area of Science:

• Neuroscience
• Cell Biology
• Biochemistry

Background:

• Oligodendrocytes exist in nonattached (B3.f) and attached (B3.fA) states.
• Adhesion induces significant morphological, ultrastructural, and biochemical changes in oligodendrocytes.

Purpose of the Study:

• To investigate the impact of oligodendrocyte adhesion on myelinogenic properties.
• To compare the synthesis of myelin and cytoskeletal proteins in attached versus nonattached cells.

Main Methods:

• Cultured B3.f and B3.fA oligodendrocytes were analyzed for protein synthesis.
• Incorporation of [3H]leucine, [35S]methionine, and [35S]cysteine was measured.
• Specific antisera were used to identify newly synthesized myelin and cytoskeletal proteins.

Main Results:

• Overall protein synthesis remained constant regardless of adhesion state or culture time.
• B3.f cells showed low synthesis of major myelin proteins but high uptake into 2',3'-cyclic nucleotide phosphodiesterase, actin, and tubulin.
• Adhesion activated synthesis and phosphorylation of myelin basic protein, and synthesis and acylation of proteolipid protein and DM-20, with increased accumulation over time.

Conclusions:

• Oligodendrocytes exhibit distinct behaviors in B3.f and B3.fA states.
• Adhesion triggers a transition from myelin-maintaining to myelin-forming oligodendrocytes.
• The presence of myelin membranes in cultures supports this conclusion.