Anti-CORO1A polyclonal antibody

Stress-responsive neuronal membrane glycoprotein M6a (Gpm6a) functions in neurite extension, filopodium and spine formation and synaptogenesis. The mechanisms of Gpm6a action in these processes are incompletely understood. Previously, we identified the actin regulator coronin-1a (Coro1a) as a putative Gpm6a interacting partner. Here, we used co-immunoprecipitation assays with the anti-Coro1a antibody to show that Coro1a associates with Gpm6a in rat hippocampal neurons. By immunofluorescence microscopy, we demonstrated that in hippocampal neurons Coro1a localizes in F-actin-enriched regions and some of Coro1a spots co-localize with Gpm6a labeling. Notably, the over-expression of a dominant-negative form of Coro1a as well as its down-regulation by siRNA interfered with Gpm6a-induced filopodium formation. Coro1a is known to regulate the plasma membrane translocation and activation of small GTPase Rac1. We show that Coro1a co-immunoprecipitates with Rac1 together with Gpm6a. Pharmacological inhibition of Rac1 resulted in a significant decrease in filopodium formation by Gpm6a. The same was observed upon the co-expression of Gpm6a with the inactive GDP-bound form of Rac1. In this case, the elevated membrane recruitment of GDP-bound Rac1 was detected as well. Moreover, the kinase activity of the p21-activated kinase 1 (Pak1), a main downstream effector of Rac1 that acts downstream of Coro1a, was required for Gpm6a-induced filopodium formation. Taken together, our results provide evidence that a signaling pathway including Coro1a, Rac1, and Pak1 facilitates Gpm6a-induced filopodium formation.

Traumatic brain injury (TBI) is a major public and socioeconomic problem throughout the world. The establishment of an effective and cost-effective TBI model for developing new therapeutic agents is challenging. Microglia are considered the resident macrophages of the central nervous system (CNS) that normally do not enter the brain. As the primary mediators of the innate immune response in the CNS, microglia play a critical role in neuroinflammation and secondary injury after TBI. In this study, we established an in vivo TBI zebrafish model using Tg(coro1a:EGFP) line where the green fluorescent protein-labeled microglia were present. We demonstrated that microglia accumulated rapidly in response to neuronal injuries. To clear away injured neurons and restore the CNS homeostasis, activated microglia secreted two types of functional cytokines, including pro-inflammatory interleukins (IL) of IL-1 beta and IL-6 and anti-inflammatory factors of IL-4 and IL-10 in the lesioned larvae. Cytidine 5 '-Diphosphocholine (CDP-choline), as an effective and clinical neuroprotective drug, could further activate microglia, expressing high levels of il-1 beta, il-6, il-4, and il-10 in the TBI model. Moreover, CDP-choline reduced neuronal apoptosis and promoted neuronal proliferation around the lesioned site. Based on these results, the TBI model established in this study represents a suitable model for developing new therapeutic agents for CNS-associated diseases.