Organisation of the tectorotundal and SP/IPS‐rotundal projections in the chick

Deng, Chao; Rogers, Lesley J.

doi:10.1002/(sici)1096-9861(19980504)394:2<171::aid-cne3>3.0.co;2-#

Cited by 76 publications

(53 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4C; n=3). The projection of the tectal efferent axons indicated that the labeled axons constitute the tectofugal pathway, and these axons had tectorotundal projections (Deng and Rogers, 1998;Wu et al, 2000;Puelles et al, 2007;Fedtsova et al, 2008). Next, we labeled tectal cells with GFP and mCherry-Nuc to follow the tangentially migrating cells.…”

Section: Movement Of Tangential Cell Migration Along the Tectal Effermentioning

confidence: 99%

NRP1-mediated Sema3A signals coordinate laminar formation in the developing chick optic tectum

2014

View full text Add to dashboard Cite

The optic tectum comprises multiple layers, which are formed by radial and tangential migration during development. Here, we report that Neuropilin 1 (NRP1)-mediated Sema3A signals are involved in the process of tectal laminar formation, which is elaborated by tangential migration. In the developing chick tectum, NRP1, a receptor for Sema3A, is expressed in microtubule-associated protein 2 (MAP2)-positive intermediate layers IV and V. Sema3A itself is a diffusible guidance factor and is expressed in the overlying layer VI. Using stable fluorescent labeling of tectal cells, we show that MAP2-positive intermediate layers are formed by the neurons that have been dispersed by tangential migration along the tectal efferent axons. When Sema3A was mis-expressed during laminar formation, local Sema3A repelled the tangential migrants, thus eliminating MAP2-positive neurons that expressed NRP1. Furthermore, in the absence of the MAP2-positive neurons, tectal layers were disorganized into an undulated form, indicating that MAP2-positive intermediate layers are required for proper laminar formation. These results suggest that NRP1-mediated Sema3A signals provide repulsive signals for MAP2-positive neurons to segregate tectal layers, which is important in order to coordinate laminar organization of the optic tectum.

show abstract

Section: Movement Of Tangential Cell Migration Along the Tectal Effermentioning

confidence: 99%

NRP1-mediated Sema3A signals coordinate laminar formation in the developing chick optic tectum

2014

View full text Add to dashboard Cite

show abstract

“…Reversed lateralization patterns after lesions of the tectotectal commissure [8] indicate that the actual functional lateralization pattern depends on a dynamic balance between left and right tectal processing [18]. Another modulator of the lateralized processing could be the tectorotundal system, which is modulated by the bed nuclei of the tecto-thalamic tract, the largest of which is the SP (nucleus subpretectalis) [2,21] (Fig. 1).…”

Section: Introductionmentioning

confidence: 99%

A morphological study of the nucleus subpretectalis of the pigeon

Freund

Güntürkün

Manns

2008

Brain Research Bulletin

View full text Add to dashboard Cite

In pigeons, the tectofugal system is functionally as well as structurally lateralized. So for example the right nucleus rotundus is less modulated by right forebrain influences than the left nucleus rotundus by the left ones. This functional lateralization pattern may depend on a dynamic balance between left and right tectal processing. Apart from inhibitory interactions at tectal level, suppressive influences might directly affect rotundal neurons by GABAergic input from a cluster of nuclei, the bed nuclei of the tecto-thalamic tract. A major afferent of these nuclei is the side branch of the tectorotundal projection which is of bilateral origin and which is involved in the regulation of ipsilateral as well as bilateral visual processing. Hence, an important role of the bed nuclei could be the interhemispheric communication and in turn the mediation of functional asymmetries. In a first step to unravel asymmetric influences of these nuclei, the present study investigated if the largest of the bed nuclei, the nucleus subpretectalis displays morphological asymmetries in the pigeon. We found that the nucleus subpretectalis in fact exhibits asymmetric cell sizes with larger cell bodies on the left side. This asymmetrical pattern was not present in dark-incubated animals indicating that cell size asymmetries within nucleus subpretectalis are induced by asymmetric photic stimulation during embryonic development.

show abstract

“…In terms of degree of tectal differentiation, turtles and lacertomorph (type 1) lizards, on one hand, and birds, on the other, can be considered as the two extremes in the organization of tectothalamic projections. In birds, which have a very highly differentiated optic tectum, tectorotundal projection neurons are restricted to the SGC, with insignificant contribution from the SGFS (Benowitz and Karten, 1976; Hunt and Künzle, 1976; Karten et al, 1997; Deng and Rogers, 1998; Luksch et al, 1998; Hellmann and Güntürkün, 1999, 2001), whereas the neurons projecting to the nucleus opticus principalis (NOP; the homologue of the reptilian and mammalian GLd) are located exclusively in the SGFS (Wild, 1989; Deng and Rogers, 1998).…”

Section: Discussionmentioning

confidence: 99%