Microglial phospholipase D4 deficiency influences myelination during brain development

Area of Science:

• Neuroscience
• Developmental Biology
• Cell Biology

Background:

• Phospholipase D4 (PLD4) is expressed in microglia during early brain development.
• Previous studies indicated PLD4's role in microglial phagocytosis and proliferation in vitro.
• The in vivo function of PLD4 in microglia remains largely uncharacterized.

Purpose of the Study:

• To investigate the in vivo role of Phospholipase D4 (PLD4) in microglial function during postnatal brain development.
• To determine the impact of PLD4 deficiency on microglial activation and myelination processes.

Main Methods:

• Generation of PLD4-deficient mice.
• Analysis of cerebella and corpus callosum at specific postnatal days (P5, P7, P10).
• Immunohistochemistry using microglial marker CD68 and myelin marker anti-myelin basic protein (MBP).

Main Results:

• PLD4-deficient microglia exhibited reduced CD68 immunoreactivity, indicating impaired activation.
• A mild but significant delay in myelination was observed in the cerebella and corpus callosum of PLD4-deficient mice at P5 and P7.
• The observed delay in myelination was transient, with no significant difference by P10.

Conclusions:

• Microglial PLD4 plays a role in microglial activation during early postnatal development.
• PLD4 deficiency in microglia transiently impairs the early stages of brain myelination.
• Microglia may utilize PLD4-dependent mechanisms to transiently support myelination during development.