TY - JOUR TI - Rho GTPase signaling directs the late stage morphogenesis of the Xenopus digestive system AU - Nascone-Yoder, Nanette M. AU - Reed, Rachel A. T2 - Developmental Biology DA - 2007/6// PY - 2007/6// DO - 10.1016/j.ydbio.2007.03.493 VL - 306 IS - 1 SP - 441 J2 - Developmental Biology LA - en OP - SN - 0012-1606 UR - http://dx.doi.org/10.1016/j.ydbio.2007.03.493 DB - Crossref ER - TY - JOUR TI - Sequence of information processing for emotions based on the anatomic dialogue between prefrontal cortex and amygdala AU - Ghashghaei, H.T. AU - Hilgetag, C.C. AU - Barbas, H. T2 - NeuroImage AB - The prefrontal cortex and the amygdala have synergistic roles in regulating purposive behavior, effected through bidirectional pathways. Here we investigated the largely unknown extent and laminar relationship of prefrontal input-output zones linked with the amygdala using neural tracers injected in the amygdala in rhesus monkeys. Prefrontal areas varied vastly in their connections with the amygdala, with the densest connections found in posterior orbitofrontal and posterior medial cortices, and the sparsest in anterior lateral prefrontal areas, especially area 10. Prefrontal projection neurons directed to the amygdala originated in layer 5, but significant numbers were also found in layers 2 and 3 in posterior medial and orbitofrontal cortices. Amygdalar axonal terminations in prefrontal cortex were most frequently distributed in bilaminar bands in the superficial and deep layers, by columns spanning the entire cortical depth, and less frequently as small patches centered in the superficial or deep layers. Heavy terminations in layers 1-2 overlapped with calbindin-positive inhibitory neurons. A comparison of the relationship of input to output projections revealed that among the most heavily connected cortices, cingulate areas 25 and 24 issued comparatively more projections to the amygdala than they received, whereas caudal orbitofrontal areas were more receivers than senders. Further, there was a significant relationship between the proportion of 'feedforward' cortical projections from layers 2-3 to 'feedback' terminations innervating the superficial layers of prefrontal cortices. These findings indicate that the connections between prefrontal cortices and the amygdala follow similar patterns as corticocortical connections, and by analogy suggest pathways underlying the sequence of information processing for emotions. DA - 2007/2// PY - 2007/2// DO - 10.1016/j.neuroimage.2006.09.046 VL - 34 IS - 3 SP - 905-923 J2 - NeuroImage LA - en OP - SN - 1053-8119 UR - http://dx.doi.org/10.1016/j.neuroimage.2006.09.046 DB - Crossref ER - TY - JOUR TI - Radial Glial Dependent and Independent Dynamics of Interneuronal Migration in the Developing Cerebral Cortex AU - Yokota, Yukako AU - Ghashghaei, H. T. AU - Han, Christine AU - Watson, Hannah AU - Campbell, Kenneth J. AU - Anton, E.S. T2 - PLoS ONE AB - Interneurons originating from the ganglionic eminence migrate tangentially into the developing cerebral wall as they navigate to their distinct positions in the cerebral cortex. Compromised connectivity and differentiation of interneurons are thought to be an underlying cause in the emergence of neurodevelopmental disorders such as schizophrenia. Previously, it was suggested that tangential migration of interneurons occurs in a radial glia independent manner. Here, using simultaneous imaging of genetically defined populations of interneurons and radial glia, we demonstrate that dynamic interactions with radial glia can potentially influence the trajectory of interneuronal migration and thus the positioning of interneurons in cerebral cortex. Furthermore, there is extensive local interneuronal migration in tangential direction opposite to that of pallial orientation (i.e., in a medial to lateral direction from cortex to ganglionic eminence) all across the cerebral wall. This counter migration of interneurons may be essential to locally position interneurons once they invade the developing cerebral wall from the ganglionic eminence. Together, these observations suggest that interactions with radial glial scaffold and localized migration within the expanding cerebral wall may play essential roles in the guidance and placement of interneurons in the developing cerebral cortex. DA - 2007/8/29/ PY - 2007/8/29/ DO - 10.1371/journal.pone.0000794 VL - 2 IS - 8 SP - e794 J2 - PLoS ONE LA - en OP - SN - 1932-6203 UR - http://dx.doi.org/10.1371/journal.pone.0000794 DB - Crossref ER - TY - JOUR TI - Reinduction of ErbB2 in astrocytes promotes radial glial progenitor identity in adult cerebral cortex AU - Ghashghaei, H. T. AU - Weimer, J. M. AU - Schmid, R. S. AU - Yokota, Y. AU - McCarthy, K. D. AU - Popko, B. AU - Anton, E. S. T2 - Genes & Development AB - Radial glial cells play a critical role in the construction of mammalian brain by functioning as a source of new neurons and by providing a scaffold for radial migration of new neurons to their target locations. Radial glia transform into astrocytes at the end of embryonic development. Strategies to promote functional recovery in the injured adult brain depend on the generation of new neurons and the appropriate guidance of these neurons to where they are needed, two critical functions of radial glia. Thus, the competence to regain radial glial identity in the adult brain is of significance for the ability to promote functional repair via neurogenesis and targeted neuronal migration in the mature brain. Here we show that the in vivo induction of the tyrosine kinase receptor, ErbB2, in mature astrocytes enables a subset of them to regain radial glial identity in the mature cerebral cortex. These new radial glial progenitors are capable of giving rise to new neurons and can support neuronal migration. These studies indicate that ErbB2 signaling critically modulates the functional state of radial glia, and induction of ErbB2 in distinct adult astrocytes can promote radial glial identity in the mature cerebral cortex. DA - 2007/// PY - 2007/// DO - 10.1101/gad.1580407 VL - 21 IS - 24 SP - 3258-3271 ER - TY - JOUR TI - Neuronal migration in the adult brain: are we there yet? AU - Ghashghaei, H. Troy AU - Lai, Cary AU - Anton, E. S. T2 - NATURE REVIEWS NEUROSCIENCE DA - 2007/2// PY - 2007/2// DO - 10.1038/nrn2074 VL - 8 IS - 2 SP - 141-151 SN - 1471-0048 ER -