The RNA helicase DDX6 regulates cell-fate specification in neural stem cells via miRNAs.
In neural stem cells (NSCs), the balance between stem cell maintenance and neuronal differentiation depends on cell-fate determinants such as TRIM32. Previously, we have shown that TRIM32 associates with the RNA-induced silencing complex and increases the activity of microRNAs such as Let-7a. However, the exact mechanism of microRNA regulation by TRIM32 during neuronal differentiation has yet to be elucidated. Here, we used a mass spectrometry approach to identify novel protein-protein interaction partners of TRIM32 during neuronal differentiation. We found that TRIM32 associates with proteins involved in neurogenesis and RNA-related processes, such as the RNA helicase DDX6, which has been implicated in microRNA regulation. We demonstrate, that DDX6 colocalizes with TRIM32 in NSCs and neurons and that it increases the activity of Let-7a. Furthermore, we provide evidence that DDX6 is necessary and sufficient for neuronal differentiation and that it functions in cooperation with TRIM32.
Stem Cell Biology and Regeneration Group, Institute of Cell Biology, ZMBE, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany Developmental and Cellular Biology Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362 Esch-Belval, Luxembourg.
Sarah
S
Nicklas
Computational Biology Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362 Esch-Belval, Luxembourg.
Satoshi
S
Okawa
Stem Cell Biology and Regeneration Group, Institute of Cell Biology, ZMBE, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany Developmental and Cellular Biology Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362 Esch-Belval, Luxembourg.
Anna-Lena
AL
Hillje
Stem Cell Biology and Regeneration Group, Institute of Cell Biology, ZMBE, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany Developmental and Cellular Biology Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362 Esch-Belval, Luxembourg.
Laura
L
González-Cano
Computational Biology Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362 Esch-Belval, Luxembourg.
Antonio
A
Del Sol
Stem Cell Biology and Regeneration Group, Institute of Cell Biology, ZMBE, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany Developmental and Cellular Biology Group, Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, L-4362 Esch-Belval, Luxembourg jens.schwamborn@uni.lu.
Jens C
JC
Schwamborn
D000818:Animals; D060565:Argonaute Proteins / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics*; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D053487:DEAD-box RNA Helicases / Q000235:genetics* / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D015151:Immunoblotting; D051379:Mice; D018345:Mice, Knockout; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D008856:Microscopy, Fluorescence; D041681:NIH 3T3 Cells; D058953:Neural Stem Cells / Q000378:metabolism*; D055495:Neurogenesis / Q000235:genetics; D011485:Protein Binding; D060066:Protein Interaction Maps / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference; D044767:Ubiquitin-Protein Ligases / Q000235:genetics* / Q000378:metabolism
C526735:Ago2 protein, mouse; D060565:Argonaute Proteins; D035683:MicroRNAs; D011518:Proto-Oncogene Proteins; C542687:mirnlet7 microRNA, mouse; D049452:Green Fluorescent Proteins; C514011:TRIM32 protein, mouse; D044767:Ubiquitin-Protein Ligases; C490616:Ddx6 protein, mouse; D053487:DEAD-box RNA Helicases