Abstract
The specification of area identities in the cerebral cortex is a complex process, primed by intrinsic cortical cues and refined after the arrival of afferent fibers from the thalamus. Little is known about the genetic control of the early steps of this process, but the distinctive expression pattern of the homeogene Emx2 in the developing cortex has prompted suggestions that it is critical in this context. We tested this hypothesis using Emx2 −/− mice. We found that the normal spectrum of cortical areal identities was encoded in these mutants, but areas with caudal–medial identities were reduced and those with anterior–lateral identities were relatively expanded in the cortex.
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Acknowledgements
We thank Marion Wassef, who provided us with H-2Z1 transgenic mice, Pier Carlo Marchisio for the gift of the anti-CKIp21 antibody, F. Rathjen for the gift of the anti-L1 antibody, Celia Leonor Pardini for in situ hybridizations and Mario Berardi for anti-L1 immunohistochemistry. This work was supported by grants from the European Community BIOTECH and BIOMED Programmes, the Telethon-Italia Programme, the Italian Association for Cancer Research (AIRC), the Armenise-Harvard Foundation, the British Council-CRUI Joint Research Program and the Wellcome Trust (grant number 059370 to J.P.).
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Mallamaci, A., Muzio, L., Chan, CH. et al. Area identity shifts in the early cerebral cortex of Emx2−/− mutant mice. Nat Neurosci 3, 679–686 (2000). https://doi.org/10.1038/76630
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DOI: https://doi.org/10.1038/76630
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