Journal Article

Induction of human neuronal cells by defined transcription factors

Ostermeier, Austin, Wernig, Marius, Südhof, Thomas C., Pang, Zhiping P., Citri, Ami, Sebastiano, Vittorio, Marro, Samuele, Vierbuchen, Thomas, Yang, Nan, Yang, Troy Q., Fuentes, Daniel R.

2011

Overview

Neurons from fibroblasts Three papers in this issue demonstrate the production of functional induced neuronal (iN) cells from human fibroblasts, a procedure that holds great promise for regenerative medicine. Pang et al . show that a combination of the three transcription factors Ascl1 (also known as Mash1 ), Brn2 (or Pou3f2 ) and Myt1l greatly enhances the neuronal differentiation of human embryonic stem cells. When combined with the basic helix–loop–helix transcription factor NeuroD1, these factors can also convert fetal and postnatal human fibroblasts into iN cells. Caiazzo et al . use a cocktail of three transcription factors to convert prenatal and adult mouse and human fibroblasts into functional dopaminergic neurons. The three are Mash1 , Nurr1 (or Nr4a2 ) and Lmx1a . Conversion is direct with no reversion to a progenitor cell stage, and it occurs in cells from Parkinson's disease patients as well as from healthy donors. Yoo et al . use an alternative approach. They show that microRNAs can have an instructive role in neural fate determination. Expression of miR-9/9* and miR-124 in human fibroblasts induces their conversion into functional neurons, and the process is facilitated by the addition of some neurogenic transcription factors. Somatic cell nuclear transfer, cell fusion, or expression of lineage-specific factors have been shown to induce cell-fate changes in diverse somatic cell types 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 . We recently observed that forced expression of a combination of three transcription factors, Brn2 (also known as Pou3f2 ), Ascl1 and Myt1l , can efficiently convert mouse fibroblasts into functional induced neuronal (iN) cells 13 . Here we show that the same three factors can generate functional neurons from human pluripotent stem cells as early as 6 days after transgene activation. When combined with the basic helix–loop–helix transcription factor NeuroD1 , these factors could also convert fetal and postnatal human fibroblasts into iN cells showing typical neuronal morphologies and expressing multiple neuronal markers, even after downregulation of the exogenous transcription factors. Importantly, the vast majority of human iN cells were able to generate action potentials and many matured to receive synaptic contacts when co-cultured with primary mouse cortical neurons. Our data demonstrate that non-neural human somatic cells, as well as pluripotent stem cells, can be converted directly into neurons by lineage-determining transcription factors. These methods may facilitate robust generation of patient-specific human neurons for in vitro disease modelling or future applications in regenerative medicine.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 631/136/142 / 631/136/532/2064 / 631/378/2571/1696 / 631/45/612/822 / Animals / Basic Helix-Loop-Helix Transcription Factors - genetics / Basic Helix-Loop-Helix Transcription Factors - metabolism / Biological and medical sciences / Cell Differentiation / Cell Line / Cells, Cultured / Cellular Reprogramming - genetics / Cellular Reprogramming - physiology / Cerebral Cortex - cytology / Coculture Techniques / DNA-Binding Proteins - genetics / DNA-Binding Proteins - metabolism / Electric Conductivity / Fibroblasts - cytology / Fibroblasts - metabolism / Fundamental and applied biological sciences. Psychology / Gene expression / Humanities and Social Sciences / Humans / letter / Membrane Potentials / Methods / Mice / multidisciplinary / Nerve Tissue Proteins - genetics / Nerve Tissue Proteins - metabolism / Neurons / Neurons - cytology / Neurons - metabolism / Physiological aspects / Pluripotent Stem Cells - cytology / Pluripotent Stem Cells - metabolism / POU Domain Factors - genetics / POU Domain Factors - metabolism / Regenerative Medicine / Rodents / Science / Science (multidisciplinary) / Stem cells / Synapses - metabolism / Transcription factors / Transcription Factors - genetics / Transcription Factors - metabolism / Transgenes / Vertebrates: nervous system and sense organs