First Author | Yabuta NH | Year | 2000 |
Journal | J Neurosci | Volume | 20 |
Issue | 15 | Pages | RC88 |
PubMed ID | 10899175 | Mgi Jnum | J:70429 |
Mgi Id | MGI:2137199 | Doi | 10.1523/JNEUROSCI.20-15-j0005.2000 |
Citation | Yabuta NH, et al. (2000) Laminar specificity of local circuits in barrel cortex of ephrin-A5 knockout mice. J Neurosci 20(15):RC88 |
abstractText | Cortical circuits are characterized by layer-specific axonal arbors. Molecular laminar cues are believed to direct the development of this specificity. We have tested the hypothesis that ephrin-A5 is responsible for preventing layer 2/3 pyramidal cell axons from branching within layer 4 (Castellani et al., 1998) by assessing the laminar specificity of axonal arbors in ephrin-A5 knockout mice. We find that in barrel cortex of knockout mice, layer 2/3 pyramidal neurons form axonal arbors specifically in layers 2/3 and 5, avoiding layer 4. This pattern of arborization is indistinguishable from that of wild-type littermates. Furthermore, we find that in wild-type mice, laminar patterns of ephrin-A5 expression differ between cortical areas despite the similarity of layer-specific local cortical circuits across areas. Most notably, ephrin-A5 is not expressed preferentially in layer 4 of wild-type mouse barrel cortex. We conclude that ephrin-A5 is not responsible for preventing the development of layer 2/3 pyramidal cell axonal arbors in layer 4 of mouse barrel cortex. These observations also suggest that if ephrin-A5 plays a role in the emergence of layer-specific circuits, that role must differ between cortical areas. |