Spatially Organized IGF1-mTOR Signaling Controls Human Forebrain Progenitor F ate Through Coordinated Transcriptional...

Area of Science:

• Neuroscience
• Developmental Biology
• Stem Cell Biology

Background:

• Human forebrain progenitor cell development relies on intrinsic genes and niche signals.
• The interplay between these cues is not fully understood.
• FOXG1+ neural progenitor cells (NPCs) are crucial for forebrain development.

Purpose of the Study:

• To investigate the role of Insulin-like Growth Factor 1 (IGF1) signaling in human forebrain progenitor cell regulation.
• To elucidate the mechanisms by which niche signals influence NPC identity and function.
• To understand the interplay between transcriptional and translational control in neurodevelopment.

Main Methods:

• Utilized pluripotent stem cell-derived forebrain models.
• Employed ribosome profiling and 5'UTR reporter assays.
• Analyzed signaling pathways including PI3K-AKT-mTOR and MEK-ERK.

Main Results:

• Identified a spatially organized, paracrine IGF1 signaling architecture regulating human FOXG1+ NPCs.
• Demonstrated that IGF1 promotes progenitor proliferation, clonal expansion, and tissue growth.
• Revealed that mTOR signaling selectively enhances translation of neurodevelopmental transcripts, including GSX1.

Conclusions:

• Discovered a human-specific regulatory mechanism involving spatially restricted IGF1-mTOR signaling.
• This pathway integrates niche signals with translational output to maintain progenitor identity and biosynthetic capacity.
• The findings offer insights into developmental resilience and potential links to autism spectrum disorder.