Neuronal Differentiation of LUHMES Cells Induces Substantial Changes of the Proteome.

Abstract

Neuronal cell lines are important model systems to study mechanisms of neurodegenerative diseases. To resemble more closely primary neurons obtained from brain, they are often differentiated into postmitotic neuron‐like cells. One example is the Lund Human Mesencephalic (LUHMES) cell line, which can differentiate into dopamine‐like neurons and is frequently used to study mechanisms of Parkinson's disease (PD) and neurotoxicity. Neuronal differentiation of LUHMES cells is commonly verified by the measurement of selected neuronal markers, but little is known about the proteome‐wide protein abundance changes during differentiation. Using mass spectrometry and label‐free quantification (LFQ), we compared the proteome of differentiated and undifferentiated LUHMES cells as well as of cultured primary murine midbrain neurons, which are mainly dopaminergic. Neuronal differentiation induced substantial changes of the LUHMES cell proteome. 18.4% of measured proteins revealed over 4‐fold abundance changes, with proliferation‐related proteins (e.g. MCMs) being strongly down‐regulated and neuronal and dopaminergic proteins, such as L1CAM and α‐synuclein (SNCA) being up to 1,000‐fold up‐regulated. Several of these proteins, including MAPT and SYN1, may be useful as new markers for experimentally validating neuronal differentiation of cultured LUHMES cells. Primary midbrain neurons were slightly more closely related to differentiated than to undifferentiated LUHMES cells, in particular with respect to the abundance of proteins related to neurodegeneration or the genetic forms of PD. In summary, our comparative proteomic analysis demonstrates that differentiated LUHMES cells are a suitable model for studies on PD and neurodegeneration and provides a resource of the proteome‐wide changes during neuronal differentiation. (ProteomeXchange identifier PXD020044)