TY - JOUR
T1 - A genome-wide RNAi screen in mouse embryonic stem cells identifies Mp1 as a key mediator of differentiation
AU - Westerman, Bart A
AU - Braat, A Koen
AU - Taub, Nicole
AU - Potman, Marko
AU - Vissers, Joseph H A
AU - Blom, Marleen
AU - Verhoeven, Els
AU - Stoop, Hans
AU - Gillis, Ad
AU - Velds, Arno
AU - Nijkamp, Wouter
AU - Beijersbergen, Roderick
AU - Huber, Lukas A
AU - Looijenga, Leendert H J
AU - van Lohuizen, Maarten
PY - 2011/12/19
Y1 - 2011/12/19
N2 - Despite intense investigation of intrinsic and extrinsic factors that regulate pluripotency, the process of initial fate commitment of embryonic stem (ES) cells is still poorly understood. We used a genome-wide short hairpin RNA screen in mouse ES cells to identify genes that are essential for initiation of differentiation. Knockdown of the scaffolding protein Mek binding protein 1 (Mp1, also known as Lamtor3 or Map2k1ip1) stimulated self-renewal of ES cells, blocked differentiation, and promoted proliferation. Fibroblast growth factor 4 (FGF4) signaling is required for initial fate commitment of ES cells. Knockdown of Mp1 inhibited FGF4-induced differentiation but did not alter FGF4-driven proliferation. This uncoupling of differentiation and proliferation was also observed when oncogenic Ras isoforms were overexpressed in ES cells. Knockdown of Mp1 redirected FGF4 signaling from differentiation toward pluripotency and up-regulated the pluripotency-related genes Esrrb, Rex1, Tcl1, and Sox2. We also found that human germ cell tumors (GCTs) express low amounts of Mp1 in the invasive embryonic carcinoma and seminoma histologies and higher amounts of Mp1 in the noninvasive carcinoma in situ precursor and differentiated components. Knockdown of Mp1 in invasive GCT cells resulted in resistance to differentiation, thereby showing a functional role for Mp1 both in normal differentiation of ES cells and in germ cell cancer.
AB - Despite intense investigation of intrinsic and extrinsic factors that regulate pluripotency, the process of initial fate commitment of embryonic stem (ES) cells is still poorly understood. We used a genome-wide short hairpin RNA screen in mouse ES cells to identify genes that are essential for initiation of differentiation. Knockdown of the scaffolding protein Mek binding protein 1 (Mp1, also known as Lamtor3 or Map2k1ip1) stimulated self-renewal of ES cells, blocked differentiation, and promoted proliferation. Fibroblast growth factor 4 (FGF4) signaling is required for initial fate commitment of ES cells. Knockdown of Mp1 inhibited FGF4-induced differentiation but did not alter FGF4-driven proliferation. This uncoupling of differentiation and proliferation was also observed when oncogenic Ras isoforms were overexpressed in ES cells. Knockdown of Mp1 redirected FGF4 signaling from differentiation toward pluripotency and up-regulated the pluripotency-related genes Esrrb, Rex1, Tcl1, and Sox2. We also found that human germ cell tumors (GCTs) express low amounts of Mp1 in the invasive embryonic carcinoma and seminoma histologies and higher amounts of Mp1 in the noninvasive carcinoma in situ precursor and differentiated components. Knockdown of Mp1 in invasive GCT cells resulted in resistance to differentiation, thereby showing a functional role for Mp1 both in normal differentiation of ES cells and in germ cell cancer.
KW - Adaptor Proteins, Signal Transducing/genetics
KW - Animals
KW - Carcinoma in Situ/genetics
KW - Cell Differentiation/physiology
KW - Cell Line
KW - Cell Proliferation
KW - Embryonic Stem Cells/cytology
KW - Fibroblast Growth Factor 4/genetics
KW - Gene Expression Regulation/physiology
KW - Genome-Wide Association Study/methods
KW - Humans
KW - Mice
KW - Mice, Knockout
KW - Neoplasms, Germ Cell and Embryonal/genetics
KW - Pluripotent Stem Cells/cytology
KW - RNA Interference
KW - Signal Transduction/physiology
UR - http://www.scopus.com/inward/record.url?scp=84855495451&partnerID=8YFLogxK
U2 - 10.1084/jem.20102037
DO - 10.1084/jem.20102037
M3 - Article
C2 - 22143885
SN - 0022-1007
VL - 208
SP - 2675
EP - 2689
JO - The Journal of experimental medicine
JF - The Journal of experimental medicine
IS - 13
ER -