Type II NSCs in the larval brain (blue, 8 per lobe: DM16 and DL12; central brain [CB], ventral nerve cord [VNC], optic lobe [OL]) divide asymmetrically to self-renew and generate an intermediate neural progenitor (INP) with each division. The INPs also divide asymmetrically to self-renew and generate a ganglion mother cell (GMC), which eventually forms two neurons and/or glia. Type II NSCs express early and late factors in a time-dependent manner starting from 0 h ALH to 120 h ALH referred to as early and late factors, respectively. In addition to temporal patterning in NSCs, INPs also express different factors in a birth-order-dependent manner along with NSC factors and give rise to a combinatorial code.
