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.