Oligodendroglial p130Cas Is a Target of Fyn Kinase Involved in Process Formation, Cell Migration and Survival

Abstract

Oligodendrocytes are the myelinating glial cells of the central nervous system. In the course of brain development, oligodendrocyte precursor cells migrate, scan the environment and differentiate into mature oligodendrocytes with multiple cellular processes which recognize and ensheath neuronal axons. During differentiation, oligodendrocytes undergo dramatic morphological changes requiring cytoskeletal rearrangements which need to be tightly regulated. The non-receptor tyrosine kinase Fyn plays a central role in oligodendrocyte differentiation and myelination. In order to improve our understanding of the role of oligodendroglial Fyn kinase, we have identified Fyn targets in these cells. Purification and mass-spectrometric analysis of tyrosine-phosphorylated proteins in response to overexpressed active Fyn in the oligodendrocyte precursor cell line Oli-neu, yielded the adaptor molecule p130Cas. We analyzed the function of this Fyn target in oligodendroglial cells and observed that reduction of p130Cas levels by siRNA affects process outgrowth, the thickness of cellular processes and migration behavior of Oli-neu cells. Furthermore, long term p130Cas reduction results in decreased cell numbers as a result of increased apoptosis in cultured primary oligodendrocytes. Our data contribute to understanding the molecular events taking place during oligodendrocyte migration and morphological differentiation and have implications for myelin formation.

MOBP levels are regulated by Fyn kinase and affect the morphological differentiation of oligodendrocytes

“…We decided to use Oli-neu cells which establish a much less complex morphology in respect to process number, length and branching and have successfully been used for the analysis of basic morphological changes previously (Binamé et al, 2013;Gonsior et al, 2014). We transfected plasmids coding for Myc-tagged MOBP71, MOBP169 and MOBP170 as well as eGFP into Oli-neu cells and fixed them 2 days later.…”

Mechanical regulation of oligodendrocyte morphology and maturation by the mechanosensor p130Cas

“…The previous paper reported that knocking‐down of p130Cas in Oli‐Neu cells decreased the thickness of their processes on poly‐L‐lysine substrate (Gonsior et al . ). On PDL‐coated dish, OL morphology was affected by either shRNA‐mediated p130Cas knockdown (Fig.…”

“…S2), similar to the previous results on poly‐L‐lysine‐coated dish (Gonsior et al . ), or shRNA‐mediated talin1 knockdown (Fig. S2).…”

“…Although p130Cas can influence OL properties even without active ECM substrates, similar to the previous results showing a reduction in p130Cas levels by siRNA affects process outgrowth, thickness of cellular processes, and migration behavior of Oli‐neu cells on poly‐L‐lysine‐coated dish (Gonsior et al . ), ECM substrates, such as laminin, might recruit various p130Cas‐interacting molecules to the focal adhesion and further facilitate the downstream signaling, which might lead to additional effects than those on poly‐lysine‐coated dish. In the previous reports, inhibition of non‐muscle myosin II (NMII) impairs Schwann cell differentiation and myelination.…”

Embryonal Fyn-associated substrate (EFS) and CASS4: The lesser-known CAS protein family members

“…For example, BCAR1 expression regulates tamoxifen resistance in breast cancer [10], and plays a crucial role in cardiovascular system and liver development [11] and osteoclast-dependent bone resorption [12]. BCAR1 supports myelin formation by oligodendrocytes in the central nervous system [13], acts as a downstream effector of serotonin (5-HT) signaling in the process of vasoconstriction [14], and serves as an important mediator for several infectious diseases including infection by Salmonella typhimurium [15], Plasmodium falciparum -associated malaria [16], pathogenic Yersinia [17, 18], and Kaposi’s sarcoma-associated herpesvirus [19]. NEDD9 known regulate neural crest cells migration during embryogenesis, which is crucial for proper neural system development [20], functions at centrosomes to activate the Aurora-A (AURKA) mitotic kinase [21], and at the basal body to activate AURKA in causing disassembly of the primary cilia [22].…”