Short communicationExpression of Cyclon/CCDC86, a novel nuclear protein, in the hippocampus of adult non-human primates

•The protein product of the gene Cyclon is expressed in adult monkey hippocampus•In cornu Ammonis, Cyclon is expressed in neurons and astrocytes.•In the dentate gyrus, Cyclon is expressed in neurons and progenitor cells.

Cyclon (cytokine-induced protein with coiled-coil domain), also known as CCDC86 (coiled-coil domain-containing protein 86), is a nuclear protein expressed in lymphocytes in mice where it regulates T-cell responses. Here we show that Cyclon/CCDC86 is expressed in the hippocampus of adult macaque monkeys, including both the hippocampus proper (cornu Ammonis) and the dentate gyrus. Cyclon/CCDC86 was localized to neurons and astrocytes in cornu Ammonis, while in the dentate gyrus the protein was also expressed in immature neurons and a very small fraction of proliferating cells. These results point to a novel expression pattern of Cyclon/CCDC86 beyond its currently known immune cell localization.