Loss of CDK5RAP2 affects neural but not non-neural mESC differentiation into cardiomyocytes.
Biallelic mutations in the gene encoding centrosomal CDK5RAP2 lead to autosomal recessive primary microcephaly (MCPH), a disorder characterized by pronounced reduction in volume of otherwise architectonical normal brains and intellectual deficit. The current model for the microcephaly phenotype in MCPH invokes a premature shift from symmetric to asymmetric neural progenitor-cell divisions with a subsequent depletion of the progenitor pool. The isolated neural phenotype, despite the ubiquitous expression of CDK5RAP2, and reports of progressive microcephaly in individual MCPH cases prompted us to investigate neural and non-neural differentiation of Cdk5rap2-depleted and control murine embryonic stem cells (mESC). We demonstrate an accumulating proliferation defect of neurally differentiating Cdk5rap2-depleted mESC and cell death of proliferative and early postmitotic cells. A similar effect does not occur in non-neural differentiation into beating cardiomyocytes, which is in line with the lack of non-central nervous system features in MCPH patients. Our data suggest that MCPH is not only caused by premature differentiation of progenitors, but also by reduced propagation and survival of neural progenitors.
a Institute of Cell Biology and Neurobiology; Charité - Universitätsmedizin Berlin; Campus Mitte ; Berlin , Germany.
Nadine
N
Kraemer
Ethiraj
E
Ravindran
Sami
S
Zaqout
Gerda
G
Neubert
Detlev
D
Schindler
Olaf
O
Ninnemann
Ralph
R
Gräf
Andrea E M
AE
Seiler
Angela M
AM
Kaindl
D000818:Animals; D018797:Cell Cycle Proteins / Q000172:deficiency*; D002454:Cell Differentiation / Q000502:physiology*; D002460:Cell Line; D002470:Cell Survival / Q000502:physiology; D053595:Embryonic Stem Cells / Q000378:metabolism*; D051379:Mice; D032383:Myocytes, Cardiac / Q000378:metabolism*; D058953:Neural Stem Cells / Q000378:metabolism*
C549613:Cdk5rap2 protein, mouse; D018797:Cell Cycle Proteins
CDK5RAP2; Cdk5rap2, Cyclin-dependent kinase-5 regulatory subunit-associated protein 2; DAPI, 4′,6-diamidino-2-phenylindole; DMEM, Dulbecco's modified Eagle's medium; FBS, fetal bovine serum; MCPH; MCPH, autosomal recessive primary microcephaly; NPCs, neuroepithelial progenitor cells; mESC, murine embryonic stem cells; mLIF, murine leukemia inhibitory factor; mental retardation; neural differentiation; primary microcephaly; qPCR, quantitative real-time PCR.; stem cell