We first examined expression patterns in the adult mouse brain for ten genes with the strongest membership for M13C, observing elevated and often exclusive expression in or near the SVZ for all of them (Supplementary Fig. 5). To provide additional confirmation for these findings, we carried out immunostaining in adult human SVZ for proteins encoded by genes with strong membership for this module (Fig. 6 and Supplementary Table 5). All of these genes were preferentially expressed in the SVZ (Fig. 6b,d–k), providing experimental validation that M13C distinguishes genes that are coexpressed in the adult subventricular neurogenic niche. Although the cellular composition and cytoarchitecture of the adult human SVZ have been extensively characterized45,46, the transcriptional programs that endow this region with its neurogenic properties are poorly understood39,40. In this system, the precise location of neural stem cells is still unknown, but it has been shown that SVZ astrocytes divide in vivo and are capable of generating neurons in the absence of exogenous growth factors in vitro45. Although it is unclear whether gene coexpression in M13C primarily reflects transcription in a single
