SEPTIN9 (SEPT9) is a filament-forming protein involved in numerous cellular processes. We have used a conditional knock out allele of Sept9 to specifically delete Sept9 in T-cells. As shown by fluorescence-activated cell sorting, loss of Sept9 at an early thymocyte stage in the thymus results in increased numbers of double-negative cells indicating that SEPT9 is involved in the transition from the double-negative stage during T-cell development. Accordingly, the relative numbers of mature T-cells in the periphery are decreased in mice with a T-cell-specific deletion of Sept9. Proliferation of Sept9-deleted CD8(+) T-cells from the spleen is decreased upon stimulation in culture. The altered T-cell homeostasis caused by the loss of Sept9 results in an increase of CD8(+) central memory T-cells.
Lassen, L. B., Füchtbauer, A., Schmitz, A., Sørensen, A. B., Pedersen, F. S., & Füchtbauer, E-M. (2013). Septin9 is involved in T-cell development and CD8(+) T-cell homeostasis. Cell and Tissue Research, 352(3), 695-705. https://doi.org/10.1007/s00441-013-1618-6