Control of Postnatal Apoptosis in the Neocortex byRhoA-Subfamily GTPases Determines Neuronal Density

• DOI: 10.1523/jneurosci.3318-09.2010
• Publication Date: 2010-03-24T17:08:00Z
• Authors: Hitomi Sanno; Xiao Shen; Nilgün Kuru; Ingo Bormuth; Kristin Bobsin; Humphrey A. R. Ga...; Dorde Komljenovic; Victor Tarabykin; Reha S. Erzurumlu; Kerry L. Tucker
• Keywords: Neocortex; Forebrain; Small GTPase

Apoptosis of neurons in the maturing neocortex has been recorded a wide variety mammals, but very little is known about its effects on cortical differentiation. Recent research implicated RhoA GTPase subfamily control apoptosis developing nervous system and other tissue types. Rho GTPases are important components signaling pathways linking extracellular signals to cytoskeleton. To investigate role neocortical differentiation, we have engineered mouse line which dominant-negative mutant (N19-RhoA) expressed from Mapt locus, such that all expressing N19-RhoA inhibitor. Postnatal expression led no major changes anatomy. Six layers developed barrels (whisker-related neural modules) formed layer IV. However, density absolute number somatosensory cortex increased by 12-26% compared with wild-type littermates. This was not explained change migration during formation rather large decrease amount neuronal at postnatal day 5, developmental maximum apoptosis. In addition, overexpression seen cause high levels These results demonstrate RhoA-subfamily members play decreased does alter cytoarchitecture patterning.