Dual-Mode Modulation of Smad Signaling by Smad-Interacting Protein Sip1 Is Required for Myelination in the Central Nervous System

Qinjie Weng, Ying Chen, Haibo Wang, Xiaomei Xu, Bo Yang, Qiaojun He, Weinian Shou, Yan Chen, Yujiro Higashi, Veronique van den Berghe, Eve Seuntjens, Steven G. Kernie, Polina Bukshpun, Elliott H. Sherr, Danny Huylebroeck, Richard R. Lu

Research output: Contribution to journalArticlepeer-review

135 Scopus citations


Myelination by oligodendrocytes in the central nervous system (CNS) is essential for proper brain function, yet the molecular determinants that control this process remain poorly understood. The basic helix-loop-helix transcription factors Olig1 and Olig2 promote myelination, whereas bone morphogenetic protein (BMP) and Wnt/β-catenin signaling inhibit myelination. Here we show that these opposing regulators of myelination are functionally linked by the Olig1/2 common target Smad-interacting protein-1 (Sip1). We demonstrate that Sip1 is an essential modulator of CNS myelination. Sip1 represses differentiation inhibitory signals by antagonizing BMP receptor-activated Smad activity while activating crucial oligodendrocyte-promoting factors. Importantly, a key Sip1-activated target, Smad7, is required for oligodendrocyte differentiation and partially rescues differentiation defects caused by Sip1 loss. Smad7 promotes myelination by blocking the BMP- and β-catenin-negative regulatory pathways. Thus, our findings reveal that Sip1-mediated antagonism of inhibitory signaling is critical for promoting CNS myelination and point to new mediators for myelin repair. Weng et al. find the transcription factor Sip1 governs myelination by modulating Smad signaling and reveal a key Sip1-induced target, Smad7, which promotes oligodendrocyte differentiation by blocking BMP and β-catenin negative regulatory pathways.

Original languageEnglish (US)
Pages (from-to)713-728
Number of pages16
Issue number4
StatePublished - Feb 23 2012

ASJC Scopus subject areas

  • General Neuroscience


Dive into the research topics of 'Dual-Mode Modulation of Smad Signaling by Smad-Interacting Protein Sip1 Is Required for Myelination in the Central Nervous System'. Together they form a unique fingerprint.

Cite this