MOAP1

Subcellular localization

basal body, transition zone, Centrosome

References: doi:10.64898/2026.01.07.698216

Functional category

• Non-motile cilium / primary cilium
• Protein processing & maturation
• Transition zone

Function

Pro-apoptotic BH3-like motif protein and BAX effector that localizes to the base of the primary cilium. Airyscan super-resolution imaging places MOAP1 at the basal body and daughter centriole, and dSTORM single-molecule localization shows the protein protruding into the basal body as far as the transition zone. MOAP1 is a yeast two-hybrid interaction partner of the transition zone protein RPGRIP1L, confirmed by co-immunoprecipitation, and in situ proximity ligation detects the RPGRIP1L-MOAP1 interaction exclusively at the ciliary base of wild-type NIH3T3 cells and not in Rpgrip1l-null cells. The ciliary proteasome continuously degrades MOAP1 at the ciliary base; loss of RPGRIP1L, TCTN1 or CEP290 reduces ciliary proteasome activity, MOAP1 accumulates at the ciliary base, and programmed cell death increases. Total cellular MOAP1 and MOAP1 at the daughter centriole are unchanged in Rpgrip1l-null cells, localizing the effect to the ciliary base. Sulforaphane rescues both the MOAP1 accumulation and the cell death, and Moap1 siRNA lowers ciliary-base MOAP1 and reduces cell death, establishing proteasomal degradation of MOAP1 at the ciliary base as the effector step. DOI 10.64898/2026.01.07.698216