HOPX regulates the development and lineage progression of human stem cell-derived outer radial glia-like cells

Although the homeodomain-only protein X (HOPX) is a well-established marker of oRG, its functional role in human cortical development remains undefined. Here, we investigated the role of HOPX in the development and lineage progression of human oRG-like cells derived from pluripotent stem cells in vitro.

Using CRISPR/Cas9-mediated gene editing, we show that HOPX loss impairs the development, expansion, and lineage potential of oRG-like cells in both two-dimensional neural cultures and three-dimensional cortical organoids. HOPX knockout neural precursors exhibit reduced proliferation, diminished neurogenesis, and premature differentiation toward astrocytic and oligodendrocytic lineages. Consistent with these findings, HOPX-deficient cortical organoids display reduced outer subventricular zone size, decreased neuronal output, and early gliogenesis.