Cerebellin-2 (CBLN2)

Cerebellin-2 (CBLN2) is a secreted synaptic organizer protein in the cerebellin family, which also includes CBLN1, CBLN3, and CBLN4[1][9]. Structurally, it contains a collagenous domain and a C-terminal TNF/C1q-like domain[2]. CBLN2 is expressed in multiple regions of the nervous system—including the cerebral cortex, hippocampus, olfactory bulb, thalamus, hypothalamus, midbrain, spinal cord, and adrenal cortex[2][5]. It forms multimeric complexes, both as homo-oligomers and heteromers with other cerebellins[2]. Functionally, CBLN2 acts as a synaptic organizer essential for the long-term maintenance (but not initial formation) of excitatory synapses in specific neuronal populations[1][9]. It forms a trans-synaptic signaling complex by binding presynaptically to neurexins and postsynaptically to GRID1 (glutamate receptor delta-1 subunit), modulating NMDA and AMPA receptor activity at hippocampal synapses[1][9]. Currently, no approved drugs are known to directly target CBLN2, and it is not a classic therapeutic target such as a receptor, enzyme, transporter, or ion channel. Its role is primarily in supporting synaptic structure and function, and mutations or altered expression are associated with certain neurodevelopmental and neuropsychiatric conditions[1][7]. No clinical biomarkers, mechanisms of drug action, or specific safety concerns are currently established for CBLN2.

Other names

cerebellin 2 precursorCBLN2UNQ1892/PRO4338