Cargando…

High Glucose–Repressed CITED2 Expression Through miR-200b Triggers the Unfolded Protein Response and Endoplasmic Reticulum Stress

High glucose in vivo and in vitro induces neural tube defects (NTDs). CITED2 (CBP/p300-interacting transactivator with ED-rich tail 2) is essential for neural tube closure. We explored the regulatory mechanism underlying CITED2 expression and its relationship with miRNA and endoplasmic reticulum (ER...

Descripción completa

Detalles Bibliográficos
Autores principales: Gu, Hui, Yu, Jingwen, Dong, Daoyin, Zhou, Qun, Wang, Jian-Ying, Fang, Shengyun, Yang, Peixin
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Diabetes Association 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4686950/
https://www.ncbi.nlm.nih.gov/pubmed/26450995
http://dx.doi.org/10.2337/db15-0108
Descripción
Sumario:High glucose in vivo and in vitro induces neural tube defects (NTDs). CITED2 (CBP/p300-interacting transactivator with ED-rich tail 2) is essential for neural tube closure. We explored the regulatory mechanism underlying CITED2 expression and its relationship with miRNA and endoplasmic reticulum (ER) stress. miR-200b levels were increased by maternal diabetes or high glucose in vitro, and this increase was abrogated by transgenic overexpression of superoxide dismutase 1 (SOD1) or an SOD1 mimetic. CITED2 was the target of miR-200b and was downregulated by high glucose. Two miR-200b binding sites in the 3′-untranslated region of the CITED2 mRNA were required for inhibiting CITED2 expression. The miR-200b mimic and a CITED2 knockdown mimicked the stimulative effect of high glucose on unfolded protein response (UPR) and ER stress, whereas the miR-200b inhibitor and CITED2 overexpression abolished high glucose–induced UPR signaling, ER stress, and apoptosis. The ER stress inhibitor, 4-phenylbutyrate, blocked CITED2 knockdown–induced apoptosis. Furthermore, the miR-200b inhibitor reversed high glucose–induced CITED2 downregulation, ER stress, and NTDs in cultured embryos. Thus, we showed a novel function of miR-200b and CITED2 in high glucose–induced UPR and ER stress, suggesting that miR-200b and CITED2 are critical for ER homeostasis and NTD formation in the developing embryo.