RT Journal Article
SR Electronic
T1 Megf10 Is a Receptor for C1Q That Mediates Clearance of Apoptotic Cells by Astrocytes
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 5185
OP 5192
DO 10.1523/JNEUROSCI.3850-15.2016
VO 36
IS 19
A1 Iram, Tal
A1 Ramirez-Ortiz, Zaida
A1 Byrne, Michael H.
A1 Coleman, Uwanda A.
A1 Kingery, Nathan D.
A1 Means, Terry K.
A1 Frenkel, Dan
A1 El Khoury, Joseph
YR 2016
UL http://www.jneurosci.org/content/36/19/5185.abstract
AB Multiple EGF-like domains 10 (Megf10) is a class F scavenger receptor (SR-F3) expressed on astrocytes and myosatellite cells, and recessive mutations in humans result in early-onset myopathy, areflexia, respiratory distress, and dysphagia (EMARDD). Here we report that Megf10-deficient mice have increased apoptotic cells in the developing cerebellum and have impaired phagocytosis of apoptotic cells by astrocytes ex vivo. We also report that cells transfected with Megf10 gain the ability to phagocytose apoptotic neurons and that Megf10 binds with high affinity to C1q, an eat-me signal for apoptotic cells. In contrast, cells expressing Megf10 with EMARDD mutations have impaired apoptotic cell clearance and impaired binding to C1q. Our studies reveal that Megf10 is a receptor for C1q and identify a novel role for Megf10 in clearance of apoptotic cells in the mammalian developing brain with potential relevance to EMARDD patients and other CNS disorders.SIGNIFICANCE STATEMENT Apoptosis is a universal homeostatic process and occurs in many disease conditions. Multiple EGF-like domains 10 (Megf10) is emerging as an essential receptor for synaptic pruning, clearance of neuronal debris, and for muscle differentiation. Here we define a novel Megf10-dependent pathway for apoptotic cell clearance and show that Megf10 is a receptor for C1q, an eat-me signal, that binds phosphatidylserine expressed on the surface of apoptotic cells. Understanding the pathways by which apoptotic cells are cleared in the CNS is relevant to many physiological and pathological conditions of the CNS.