Yes-associated protein regulates microgravity-induced primary cilia disassembly and osteogenic differentiation inhibition in osteoblasts
Zhang Yanan
Hua Junrui
Zhang Tianyi
Wei Wenjun
Wang Jufang
He Jinpeng
Abstract：Objective To investigate the effects of simulated-microgravity on the osteogenic differentiation,primary cilia status,cytoskeleton structure,and the YAP(Yes-associated protein)expression in primary osteoblasts.Methods Primary osteoblasts were isolated from the skull bones of neonatal Wistar rats and cultured in random positioning machine system to simulate the cellular effects of microgravity.The calcified nodules were stained with Arlizarin to assess the cellular mineralization ability,the primary cilia and cytoskeleton were detected by immunofluorescence staining of Arl13b/γ-Tubulin and α-Tubulin,respectively,and the expression of YAP was measured by western blot.Results The cellular osteogenic differentiation were markedly suppressed after treated with simulated microgravity for 24 h,and the ciliated cells decreased from(58.44±3.65)%to(15.76±1.84)%in parallel with a decline of average cilium length from(3.19±0.51)μm to(1.59±0.46)μm.In addition,simulated microgravity induced disassembly of microtubules.Notably,simulated microgravity interfered YAP expression and the inhibition of YAP into nucleus.Furthermore,knockdown of YAP expression in osteoblasts notably reduced primary cilia expression and inhibited osteogenic differentiation.Conclusion Primary cilia is a key organelle of osteoblasts in sensing microgravity and regulating osteogenic differentiation.Interference with YAP expression and inhibition of nuclear YAP entry may play an important role in the deaggregation of primary cilia induced by microgravity.
Keywords：microgravitybone lossosteogenic differentiationcytoskeletonYAP
Publication Date：2025-02-14
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)