A Novel Function of RING Finger Protein 10 in Transcriptional Regulation of the Myelin-Associated Glycoprotein Gene and Myelin Formation in Schwann Cells

Abstract

Myelin-associated glycoprotein (MAG) has been detected in Schwann cells prior to the onset of myelination, suggesting its functions in the initiation of myelination. However, transcriptional regulatory mechanisms of MAG remain to be elucidated. Here, we analyzed the promoter of the MAG gene by using luciferase reporter systems in the primary rat Schwann cells. We identified a novel cis-acting element located 160 bp upstream from the MAG transcription initiation site. Using the identified cis-element as a bait, we performed yeast one-hybrid screening and isolated a cDNA encoding a RNF10 as a putative trans-acting protein. When overexpressed in Schwann cells, RNF10 enhanced the activity of the MAG promoter. When RNF10 expression in Schwann cells was knocked down by siRNA, endogenous MAG mRNA and protein expression decreased. Furthermore, we evaluated myelin synthesis using Schwann cell-DRG neuron cocultures. When Schwann cells were infected with retrovirus expressing RNF10 siRNA, myelin formation was inhibited. These data suggest that RNF10 regulates MAG expression and is required for myelin formation.

Recombinant Human Myelin-Associated Glycoprotein Promoter Drives Selective AAV-Mediated Transgene Expression in Oligodendrocytes

“…We therefore decided to also investigate the proximal 1.5 kb of the long fragment since this fragment was devoid of these motifs but contained binding sites for myelin cell lineage factors Oligodendrocyte Transcription Factor 1 (Olig1) and SRY-Box 10 (Sox10) and an evolutionary highly conserved sequence (Wang et al, 2014 ). Finally, we also selected the proximal 300 bp fragment for further characterization as it contains evolutionary conserved binding sites for myelin gene regulatory factor (MRF) and Ring Finger Protein 10 (RNF10), critical activators of myelination in oligodendrocytes or Schwann cells, respectively (Hoshikawa et al, 2008 ; Emery et al, 2009 ; Bujalka et al, 2013 ). Another conserved DNA stretch was located between −1315 to −1176.…”

Nicotinic acetylcholine receptors mediate donepezil‐induced oligodendrocyte differentiation

“…The rat MAG promoter, from −2752 to +78 upstream of the luciferase coding region in pGL3‐Basic vector was provided by Dr T. Ogata (Hoshikawa et al . ). Cells were plated at a density of 2.5 × 10 5 cells/well in 4‐well dishes (TOHO, Tokyo, Japan) the day before transfection.…”

Genomic characterisation and conservation genetics of the indigenous Irish Kerry cattle breed

“…A single gene was also located within the BTA16 selection peak—the dorsal inhibitory axon guidance protein gene ( DRAXIN ), which encodes a protein that regulates axon guidance, neural circuit formation and vertebrate brain development (Islam et al, 2009; Shinmyo et al, 2015). Twenty-four genes were located within the BTA17 selection peak, including BICDL1 , RAB35 and RNF10 , which have been associated with neurobiology and brain development (Hoshikawa et al, 2008; Schlager et al, 2010; Villarroel-Campos et al, 2016) and SIRT4 and COQ5 that function in cellular metabolism (Kawamukai, 2015; Elkhwanky and Hakkola, 2017). Six genes were located within the BTA28 selection peak, including, most notably, the Rho GTPase activating protein 22 gene ( ARHGAP22 ), which has recently been associated with bovine fertility as an mRNA expression biomarker for oocyte competence in cumulus cells (Melo et al, 2017).…”