May be a component of the linker structure that bridges the ciliary membrane and peripheral singlet microtubules. Expressed exclusively at the cilium tip where it localizes between the cell membrane and peripheral A-subfibers. Expressed exclusively in ciliated epithelial cells. Detected in ciliated epithelium of trachea and oviduct (at protein level). Expression gradually increases during in vitro ciliogenesis. 'Sentan' means 'tip' in Japanese. Belongs to the S-100 family.