What a piece of work is ARHGAP11B, how noble in reason, how infinite in faculty!

Human-specific gene ARHGAP11B promotes basal progenitor amplification and neocortex expansion
by Wieland B. Huttner, Marta Florio, Mareike Albert, et al.
Science DOI: 10.1126/science.aaa1975
Published Online February 26 2015

Evolutionary expansion of the human neocortex reflects increased amplification of basal progenitors in the subventricular zone, producing more neurons during fetal corticogenesis. Here, we analyze the transcriptomes of distinct progenitor subpopulations isolated by a cell polarity-based approach from developing mouse and human neocortex. We identify 56 genes preferentially expressed in human apical and basal radial glia that lack mouse orthologs. Among these, ARHGAP11B has the highest degree of radial glia-specific expression. ARHGAP11B arose from partial duplication of the Rho GTPase-activating-protein–encoding ARHGAP11A on the human lineage after separation from the chimpanzee lineage. Expression of ARHGAP11B in embryonic mouse neocortex promotes basal progenitor generation and self-renewal, and can increase cortical plate area and induce gyrification. Hence, ARHGAP11B may have contributed to evolutionary expansion of human neocortex.