CLCF1
CLCF1 (cardiotrophin-like cytokine factor 1), also called novel neurotrophin-1 (NNT-1) or B-cell stimulating factor-3 (BSF-3), is a secreted IL-6 family cytokine with a four-helix bundle fold. On its own CLCF1 is poorly secreted; it circulates as a composite cytokine bound to the soluble receptor component CRLF1 (neuropoietin), and the complex signals through the tripartite CNTF receptor system of CNTFR, LIFR and gp130, activating JAK/STAT3. CLCF1 supports motor neuron and sympathetic neuron survival and promotes B-cell development. Biallelic CLCF1 mutations cause cold-induced sweating syndrome type 2, highlighting its essential role in autonomic and motor function.
