preglomerular complex

Forebrain > Diencephalon > Preglomerular Complex

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Schematic showing the position of the preglomerular complex in sagittal, horizontal and coronal sections through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Description

“The thalamus proper is less prominent in zebrafish than in mammals. This is the case because teleosts possess a preglomerular complex, an elaborated migrated agglomeration of nuclei related to the posterior tuberculum absent in mammals. In fact, the preglomerular complex serves as a predominant sensory relay station in the teleostean diencephalon (Wullimann and Northcutt, 1990; Northcutt, 2008; Yamamoto and Ito, 2008).”(Mueller, 2012). The PG complex in teleosts receives sensory input from several sensory modalities including visual, auditoy, lateral line, gustatory and potentially somatosensory (Bloch et al., 2020).

"The preglomerular complex consists of the anterior, the lateral, the medial, and the caudal preglomerular nuclei (PGa, PGl, PGm, PGc) and additionally the tertiary gustatory nucleus (TGN), the posterior thalamic (P), and the subglomerular (SG) nucleus. These nuclei have been interpreted as migrated derivatives of the embryonic posterior tuberculum (Braford and Northcutt, 1983; Northcutt, 2008). They serve as sensory relay stations projecting to different parts of the pallium, comparable to sensory thalamic nuclei in mammals. Based on their projection patterns to pallial parts of the adult zebrafish telencephalon and on expression patterns of pax6 in larval zebrafish, these nuclei have been interpreted as homologous to thalamic nuclei of mammals (Yamamoto and Ito, 2008)." (Mueller., 2012)

The lateral preglomerular nucleus receives visual information from the optic tectum and projects to the pallium. This ascending visual circuit has been compared to the ascending thalamocortical visual pathway in mammals and other vertebrates. Some new work on the development of the preglomerular complex has shown that the majority of PG cells are derived from the midbrain rather than from the forebrain as the thalamus is in amniotes suggesting that the PG complex may not be homologous to the thalamus of amniotes (Bloch et al., 2020).

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In the adult

The preglomerular complex is part of the wider thalamus.

Schematic adapted from Mueller 2012 showing the nuclei that comprise the wider thalamus. 

Abbreviations: A, anterior thalamic nucleus; CPo, centroposterior thalamic nucleus; D, dorsal telencephalon (pallium); DP, dorsoposterior thalamic nucleus; EmT, eminentia thalami; Hyp, hypothalamus; Hb, habenula; I, intermediate thalamic nucleus; IC, intercalated thalamic nucleus; OB, olfactory bulb; OT, optic tectum; P, posterior thalamic (preglomerular) nucleus; PG, preglomerular complex; PGa, anterior preglomerular nucleus; PGc, caudal preglomerular nucleus; PGl, lateral preglomerular nucleus; PGm, medial preglomerular nucleus; PO, preoptic region; PrT, pretectum; PVO, paraventricular organ; SG, subglomerular nucleus; TGN, tertiary gustatory nucleus; TPp, periventricular nucleus of posterior tuberculum; TPm, migrated nucleus of posterior tuberculum; V,ventral telencephalon (subpallium); VL, ventrolateral thalamic nucleus; VM, ventromedial thalamic nucleus.

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The preglomerular complex is formed of 7 different nuclei. The anterior group is formed by the anterior preglomerular nucleus (PGa), lateral preglomerular nucleus (PGl) and the medial preglomerular nucleus (PGm). The posterior group includes the tertiary gustatory nucleus (TGN), subglomerular nucleus (SG), posterior thalamic (preglomerular) nucleus, (P) and the caudal preglomerular nucleus (PGc).

Nuclei that make up the preglomerular complex.

Preglomerular Complex: Anterior Group

Preglomerular Complex: Posterior Group

level of transverse section

Top = dorsal view; Bottom = lateral view of an adult zebrafish brain. Line marks level of the transverse sections in previous schematics.

Positions of preglomerular nuclei taken from Neuroanatomy of the Zebrafish Brain (Wullimann et al., 1996).

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Ontology
 

is part of: diencephalon, posterior tuberculum.

has parts: P, posterior thalamic(preglomerular)nucleus, PGa, anterior preglomerular nucleus; PGc, caudal preglomerular nucleus; PGl, lateral preglomerular nucleus; PGm, medial preglomerular nucleus; TGN, tertiary gustatory nucleus;SG, subglomerular nucleus.

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ZFIN

OLS Tree Diagram

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Anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

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Key Publications

Bloch et al.
Non-thalamic origin of zebrafish sensory nuclei implies convergent evolution of visual pathways in amniotes and teleosts.
Elife, 2020 vol. 9 pp. 233-27

Thomas Mueller
What is the Thalamus in Zebrafish?
Front Neurosci. 2012; 6: 64.

Yamamoto, N., and Ito, H.
Visual, lateral line, and auditory ascending pathways to the dorsal telencephalic area through the rostrolateral region of the lateral preglomerular nucleus in cyprinids.
J. Comp. Neurol. 2008. 508, 615–647.

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pineal complex/epiphysis

Forebrain > Diencephalon > Epithalamus> Pineal Complex

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Schematic showing the position of the pineal/epiphysis in sagittal, horizontal and coronal sections through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Description

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ontology

is part of:
forebrain, epithalamus

has parts:
epiphysis/pineal organ
parapineal

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ZFIN

OLS Tree Diagram

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Anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

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habenulae

Forebrain > Diencephalon> Epithalamus> Habenulae

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Schematic showing the position of the habenulae in sagittal, horizontal and coronal sections through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Introduction

The habenulae are part of a highly conserved conduction system, the dorsal-diencephalic conduction system (DDC), that interconnects sites in the limbic forebrain with the ventral midbrain and hindbrain (Bianco & Wilson, 2009). 

 The paired habenula nuclei exhibit several left-right asymmetries.  Displaying differences in the proportion of neuronal subtypes with distinct patterns of gene expression, axon terminal morphology and connectivity (Bianco et al, 2008, Roussigne at al, 2009).

 The habenulae have been shown to be important in a range of behaviours.  Their regulation of monaminergic activity in the midbrain is important for the modulation of fear behaviours, avoidance learning and attention (Agetsuma et al, 2010).  As would be expected of a regulator of monoaminergic activity they also have been implicated in psychosis, depression, anxiety, schizophrenia and addictive behaviours.  They also play a role in circadian rhythms, sleep initiation and duration and reproductive and maternal behaviours (Bianco & Wilson, 2009, Hikosaka, 2010).

The neuroanatomical asymmetries of the habenula can also lead to a lateralisation of certain behaviours (Barth et al, 2005).

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Neuroanatomy

 The habenulae are spheroid nuclei.  Habenular neurons are mono-polar.. The cells direct their dendrites inwards forming an internal neuropil core that the cell bodies surround.

Single-depth confocal section through the habenulae of a 4 dpf Tg(ET16:GFP) transgenic larva in which a subset of habenular neurons express GFP. In each nucleus the neuronal somata are arranged as ovoid shells surrounding a central neuropil domain. It is in this domain that neurons elaborate their dendritic arbors(Image courtesy of Isaac Bianco taken from Bianco et al, 2008).

A Left habenular neuron visualised by focal electroporation with a construct driving the expression of membrane GFP. Habenular cells have a rounded nucleus and are mono polar, projecting their dendrites inwards to form the dense neuropil of the habenulae (Image courtesy of Isaac Bianco taken from Bianco et al, 2008).

 In the zebrafish, the left habenula receives projections from the left-sided parapineal organ that promotes the elaboration of left sided habenular identity (Bianco et al, 2008).

At later stages, in both habenulae a dorsal and a ventral habenular subnucleus(vHb) can be distinguished. The ventral subnucleus is homologous to the lateral mammalian habenula and the dorsal habenula is homologous to the medial mammalian habenula.  The dorsal habenula can be further subdivided into lateral and medial subnuclei (dHbL,dHBM). (Amo et al, 2010). 

A dorsal view of the epithalamus showing the left sided parapineal nucleus innervating the left habenular. The left-sided parapineal organ that promotes the elaboration of left sided habenular identity (Image courtesy of Miguel Concha, Concha et al, 2003).

Schematic showing a transverse section through the adult habenular nuclei. This schematic shows the arrangment of the dorsal and ventral habenular subnuclei, the dorsal nucleus is further subdivided into medial and lateral subnuclei (See Development section to see the morphogenetic movements that result in this adult arrangement)(Schematic adapted from Amo et al, 2010).

This Figure shows a dorsal view of a 4dpf Tg(mp558b:GFP) embryo labelled with anti-acetylated tubulin(red) and SV2(blue). The anti-acetylated tubulin antibody labels axonal tracts and the SV2 antibody labels synaptic neuropil. This line expresses GFP only in the left dHbL nuclei. In panels B & C the same confocal stack has been rendered into 3D. By rotating the stack to the right we can see the synaptic neuropil of the three subnuclei and their relative positions at this stage of development. In panel C, the region that would be GFP positive is indicated by the dashed white line.

 The habenulae are part of a system that relays information from the telencephalon and entopeduncular nucleus in the forebrain to the interpeduncular nucleus and to the raphe nucleus located in the midbrain/hindbrain.  The afferent fibres from the telencephalon/ entopeduncular nucleus reach the habenulae via the stria medullaris. The projections of the habenula to the interpeduncular nucleus and raphe nucleus travel in the fasciculus retroflexus.

 In zebrafish there are obvious anatomical asymmetries between the left and right habenulae. This can be seen in the differing size and shape of the neuropil in the left and right habenulae.  The dHbM and dHbL subnuclei also have different size ratios on the left and the right and innervate different regions of the IPN. While the dHbm subnucleus is the main source of projections to the ventral region of the IPN the dHbL subnucleus projects mainly to the dorsal IPN (Agetsuma et al, 2010).

Dorsal view of a 4dpf wt embryo labelled with sytox nucleic acid stain, anti-acetylated tubulin(red) and SV2(blue). The spheroid nuclei of the habenulae can be seen surrounding a dense core of neuropil that is larger in the left habenular than in the right and differently shaped.

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Left-right asymmetries in the telencephalon-habenula-IPN pathway.

(a) Schematic of a 4 dpf larval zebrafish brain. The habenular (Hb) nuclei receive afferent inputs from nuclei in the telencephalon (Tel) via the stria medullaris and diencephalon (not shown). Habenular neurons send efferent projections via the fasciculus retroflexus (FR) to the interpeduncular nucleus (IPN) in the ventral mid-brain. The L habenula predominantly innervates the dIPN and makes less substantial projections to the vIPN whereas the vast majority of R-sided axons terminate in the vIPN. In addition to the habenulae, the epithalamus contains the pineal complex, comprising the photoreceptive pineal (P) and parapineal (pp) nuclei. The parapineal is located on the L side of the dorsal midline and projects efferent axons that exclusively innervate the L habenula. (b) Neuroanatomical asymmetries in the epithalamus. Anti-acetylated tubulin immunostaining (red) reveals the L habenula displays a greater density of neuropil, especially in the dorso-medial aspect of the nucleus (arrow). The pineal (blue) and parapineal (green) nuclei are visualized by expression of GFP in a Tg(foxD3:GFP) transgenic larva. Parapineal efferent axons predominantly terminate in the asymmetric neuropil of the L habenula. (c) Three-dimensional reconstruction of habenular axon terminals in the ventral midbrain. L-sided axons were labelled with DiD (red) and R-sided axons with DiI (green). The dIPN is almost exclusively innervated by L-sided axons, whereas the ventral target receives a majority of R-sided inputs. All panels show dorsal views, anterior top. pc, posterior commissure;

Single cell electroporations of habenula neurons showed that habenular efferents have two distinct patterns of axonal arborisation in their terminals in the IPN. Axons coming from the left-sided habenula neurons terminate predominantly in the dorsal IPN. Three-dimensional reconstructions of these L-typical arbors reveal them to be formed like a 'domed crown' with branches extending over considerable DV depth.  Their terminals circle the IPN and extend colaterals directed internally into the IPN.Right-sided habenula neurons predominantly terminate in the ventral IPN. Their axon terminals also surround the IPN but in a more ovoid-like shape “reminiscent of an electromagnetic coil. They look a lot flatter than the L-typical arbors, extending over less depth.  The branches of the right axons concentrate more in the periphery, with relatively few branches in the centre of the IPN. Although these single cell electroporation experiments have not yet been carried out in transgenic lines labeling specific habenula subnuclei the results of Bianco et al, 2008 correlate well with later studies describing the innervation of the IPN by the lateral and medial dorsal habenula nuclei.

Habenular neurons have a stereotypical unipolar morphology and their axons terminate in spiral-shaped arbors that display multiple midline crossing. (Left) Three-dimensional reconstruction showing a R habenular (rHb) projection neuron in an intact 4 dpf larval zebrafish brain. Arrow indicates direction of axonal projection within the FR, from the rHb to the IPN. (Centre and Right) Confocal z-projection within the IPN showing a single axonal arbor elaborated by a L habenular projection neuron(centre) labeled by focal electroporation. The arbor crosses the ventral midline (dotted line) multiple times. Branches can also reverse direction such that they encircle the IPN in opposite senses. These arbors are shaped like a domed crown and arborize over a considerable DV extent. (Right) Shows an example of a R typical arbour, Which are considerably flatter. (Image provided by Isaac Bianco taken from Bianco et al, 2008)

 From bulk labeling experiments, results suggest that the left habenular nucleus innervates the dorsal IPN and the right habenular nucleus innervates the ventral IPN. In Agetsuma et al, 2010 the habenula-IPN projection pattern in the adult is shown. Instead of bulk labeling the entire habenula nuclei with DiI, the dHbL and dHbm and their efferents are labeled in the double transgenic Tg(narp:GAL4VP16; UAS:DsRed2; brn3a- hsp70:GFP) fish. In the adult the Narp expression selectively labels the dHbL subnucleus, which is much larger on the left-side. Axons from this subnucleus terminate predominantly in the dorsal IPN. The Brn3a:GFP expression labels the dHbM,  the terminals of these nuclei innervate the ventral IPN primarily. In the adult there is also an intermediate zone of the IPN where in the Tg(narp:GAL4VP16; UAS:DsRed2; brn3a- hsp70:GFP) red and green terminals overlap. The application of anterograde tracers to the dIPN showed that efferents from this region project to the dorsal raphé and continue on to terminate in the griseum central (GC)which corresponds to the mammalian periaqueductal gray (PAG), dorsal tegmental nucleus and nucleus incertus. These areas in mammals have been linked to the control of behaviour in fearful or stressful conditions. Manipulation of the dHbL-dIPN pathway with tetanus toxin light chain biased the fish towards a freezing behaviour as opposed to the normal flight response when subjected to cued fear-conditioning. This corroborates that in zebrafish the dHbL-dIPN –GC pathway, as in mammals, is involved in the modification of behavioral responses in an experience-dependent manner (Agetsuma et al, 2010).

 Unlike the dorsal habenular nuclei the ventral habenular nuclei are symmetric, the vHb projects via the fasiculus retroflexus(FR) to the ventral part of the median raphé. The efferents travelling in the FR are arranged with the dHb efferents forming the core of the tract while the vHb efferents form a sheath surrounding them(Amo et al, 2010). 

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Habenula Afferent areas

Schematics showing a summary of the main afferent areas to the habenula from Turner et al., 2016.

(K: outline of the brain in lateral view, L: boxes diagram). (K) The brain nuclei that project to the habenula are shown as colored areas. (L) Boxes represent main nuclei projecting to the habenula, while arrows represent projections. Asymmetric projection from the parapineal (PP) to left habenula (lHB) is shown with a blue arrow. Asymmetric projection from mitral cells of the olfactory bulbs (OB) to right habenula (rHB) is shown with a pink arrow. All other afferent areas that seem to innervate both left and right habenula are represented with black arrows.

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 Development

By observing the expression patern of the vHB specific marker Diamine Oxidase(dao) throughout development it is possible to see that the dorso-ventral orientation of the fish habenula is a result of a morphogenetic process. At 5dpf expression of dao in the primordium is lateral to the dorsal habenular nuclei. This region then migrates ventro-medially to result in the arrangement we observe in the adult zebrafish.

Schematic showing the relative positions of the dosal and ventral habenulae subnuclei at different stages of development.

At 5dpf the vHb subnucleus is lateral to the dorsal habenular nuclei in the habenular primordium. This region then migrates ventro-medially to result in the arrangement we observe in the adult zebrafish. dHb (blue) and vHb(orange)(Schematic adapted from Amo et al, 2010).

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Ontology
 

is part of: epithalamus, diencephalon, forebrain

has parts: dorsal habenula nucleus, ventral habenula nucleus

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ZFIN

OLS Tree Diagram

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Key Publications

Amo et al, 2010  http://www.ncbi.nlm.nih.gov/pubmed/20107084.

Concha et al, 2003 http://www.ncbi.nlm.nih.gov/pubmed/12895418

Bianco et al, 2008 http://www.ncbi.nlm.nih.gov/pubmed/18377638

Bianco & Wilson, 2009  http://www.ncbi.nlm.nih.gov/pubmed/19064356

Hendricks & Jesuthasan 2007 http://www.ncbi.nlm.nih.gov/pubmed/17394162

Agetsuma et al, 2010   http://www.ncbi.nlm.nih.gov/pubmed/20935642

Hikosaka, 2010 http://www.ncbi.nlm.nih.gov/pubmed/20559337

Turner et al, 2016 https://www.frontiersin.org/articles/10.3389/fncir.2016.00030/full

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preoptic area

Forebrain > Diencephalon> Preoptic Area

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Schematic showing the position of the preoptic area in sagittal, horizontal and coronal sections through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Description

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Ontology
 

is part of:

has parts:

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ZFIN

OLS Tree Diagram

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Anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

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posterior tuberculum

Forebrain > Diencephalon > Posterior Tuberculum

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Schematic showing the position of the posterior tuberculum split into dorsal and ventral regions in sagittal, horizontal and coronal sections through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Description

“The posterior tuberculum and the preglomerular complex are two dominant structures in the basal diencephalon of zebrafish, which also have no apparent counterparts in amniote tetrapods like birds and mammals. Yet, a large posterior tuberculum is present in jawless vertebrates (lampreys), cartilaginous fishes (sharks and manta rays), lungfish, and amphibians (Nieuwenhuys et al., 1998). In mammals, the basal plate derivatives of prosomere two and three are homologous to the dorsal and ventral posterior tubercular fields of developing zebrafish (Wullimann and Puelles, 1999). In the mature zebrafish brain, the posterior tuberculum comprises the periventricular nucleus of the posterior tuberculum with its characteristic large pear-shaped dopaminergic cells, the paraventricular organ, and the posterior tuberal nucleus. All of them are intercalated between prethalamus and hypothalamus (Rupp et al., 1996; Wullimann et al., 1996). Some of these dopaminergic neurons found in the posterior tuberculum of zebrafish project to the subpallium and have been compared and homologized with an anteriormost diencephalic, not mesencephalic, division of the mammalian ascending mesodiencephalic dopaminergic groups A8–A10 in mammals (Wullimann and Rink, 2001; Rink and Wullimann 2002).” (Mueller, 2012).

Schematic adapted from Mueller 2012 showing the nuclei that comprise the wider thalamus. 

Abbreviations: A, anterior thalamic nucleus; CPo, centroposterior thalamic nucleus; D, dorsal telencephalon (pallium); DP, dorsoposterior thalamic nucleus; EmT, eminentia thalami; Hyp, hypothalamus; Hb, habenula; I, intermediate thalamic nucleus; IC, intercalated thalamic nucleus; OB, olfactory bulb; OT, optic tectum; P, posterior thalamic (preglomerular) nucleus; PG, preglomerular complex; PGa, anterior preglomerular nucleus; PGc, caudal preglomerular nucleus; PGl, lateral preglomerular nucleus; PGm, medial preglomerular nucleus; PO, preoptic region; PrT, pretectum; PVO, paraventricular organ; SG, subglomerular nucleus; TGN, tertiary gustatory nucleus; TPp, periventricular nucleus of posterior tuberculum; TPm, migrated nucleus of posterior tuberculum; V,ventral telencephalon (subpallium); VL, ventrolateral thalamic nucleus; VM, ventromedial thalamic nucleus.

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Ontology
 

is part of:

has parts:

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ZFIN

OLS Tree Diagram

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Anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Transgenic Lines that label this brain region

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Key Publications

Thomas Mueller
What is the Thalamus in Zebrafish?
Front Neurosci. 2012; 6: 64.

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hypothalamus

Forebrain > Diencephalon> Hypothalamus

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Schematic showing the position of the hypothalamus in sagittal, horizontal and coronal sections through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Description

The hypothalamus is the largest and most ventral division of the diencephalon. It's name means "below the thalamus" however this anatomical position applies only to the rostral regions as the more caudal areas are actually below the mesencephalic tegmentum. The hypothalamus arises near the end of the segmentation period (Kimmel et al, 2005) and it gives rise the tuberal nuclei, the inferior hypothalamic lobes and the neurohypophysis of the adult (Meek and Nieuwenhuys, 1998). The hypothalamus is the master regulator of endocrine and autonomic function within the brain (Mathieu et al, 2002).

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Subdivisions of the hypothalamus in larval zebrafish. Schematics based on the 3D anatomical segmentation by the ZBB.

Ontology
 

is part of: diencephalon

has parts: dorsal hypothalamic zone, intermediate hypothalamus, medial tuberal portion

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Anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

OLS Tree Diagram

ZFIN

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prethalamus

Forebrain > Diencephalon> Prethalamus

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Schematic showing the position of the prethalamus in sagittal, horizontal and coronal sections through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Description

synonym: ventral thalamus

Schematic adapted from Mueller 2012 showing the nuclei that comprise the wider thalamus. 

Abbreviations: A, anterior thalamic nucleus; CPo, centroposterior thalamic nucleus; D, dorsal telencephalon (pallium); DP, dorsoposterior thalamic nucleus; EmT, eminentia thalami; Hyp, hypothalamus; Hb, habenula; I, intermediate thalamic nucleus; IC, intercalated thalamic nucleus; OB, olfactory bulb; OT, optic tectum; P, posterior thalamic (preglomerular) nucleus; PG, preglomerular complex; PGa, anterior preglomerular nucleus; PGc, caudal preglomerular nucleus; PGl, lateral preglomerular nucleus; PGm, medial preglomerular nucleus; PO, preoptic region; PrT, pretectum; PVO, paraventricular organ; SG, subglomerular nucleus; TGN, tertiary gustatory nucleus; TPp, periventricular nucleus of posterior tuberculum; TPm, migrated nucleus of posterior tuberculum; V,ventral telencephalon (subpallium); VL, ventrolateral thalamic nucleus; VM, ventromedial thalamic nucleus.

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Ontology
 

is part of: diencephalon, thalamus

has parts:

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ZFIN

OLS Tree Diagram

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Anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Transgenic Lines that label this brain region

Antibodies that label this brain region

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Key Publications

Thomas Mueller
What is the Thalamus in Zebrafish?
Front Neurosci. 2012; 6: 64.

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thalamus

Forebrain > Diencephalon>Thalamus

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Schematic showing the position of the ? in sagittal, horizontal and coronal sections through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Description

Schematic adapted from Mueller 2012 showing the nuclei that comprise the wider thalamus. 

Abbreviations: A, anterior thalamic nucleus; CPo, centroposterior thalamic nucleus; D, dorsal telencephalon (pallium); DP, dorsoposterior thalamic nucleus; EmT, eminentia thalami; Hyp, hypothalamus; Hb, habenula; I, intermediate thalamic nucleus; IC, intercalated thalamic nucleus; OB, olfactory bulb; OT, optic tectum; P, posterior thalamic (preglomerular) nucleus; PG, preglomerular complex; PGa, anterior preglomerular nucleus; PGc, caudal preglomerular nucleus; PGl, lateral preglomerular nucleus; PGm, medial preglomerular nucleus; PO, preoptic region; PrT, pretectum; PVO, paraventricular organ; SG, subglomerular nucleus; TGN, tertiary gustatory nucleus; TPp, periventricular nucleus of posterior tuberculum; TPm, migrated nucleus of posterior tuberculum; V,ventral telencephalon (subpallium); VL, ventrolateral thalamic nucleus; VM, ventromedial thalamic nucleus.

synonym: dorsal thalamus

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Ontology
 

is part of: diencephalon

has parts:

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ZFIN

OLS Tree Diagram

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Anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Transgenic Lines that label this brain region

Antibodies that label this brain region

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Key Publications

Thomas Mueller
What is the Thalamus in Zebrafish?
Front Neurosci. 2012; 6: 64.

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Back to Forebrain

epithalamus

Forebrain > Diencephalon>Epithalamus

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Schematic showing the position of the epitahlmus in a coronal section through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Description

The epithalamus forms the roof of the diencephalon and consists of the pineal organ, parapineal organ and the habenulae.

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Ontology
 

is part of:

has parts:

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ZFIN

OLS Tree Diagram

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Anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Transgenic Lines that label this brain region

Antibodies that label this brain region

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Key Publications

Thomas Mueller
What is the Thalamus in Zebrafish?
Front Neurosci. 2012; 6: 64.

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Back to Forebrain

pretectum

Forebrain > Diencephalon> Pretectum

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Schematic showing the position of the pretectum in sagittal, horizontal and coronal sections through the zebrafish brain.
Based on the anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Abbreviations: Ce, cerebellar plate; D, dorsal telencephalon/pallium; E, epiphysis; EmT, eminentia thalami; Hb, habenula; Hyp, hypothalamus; MO, medulla oblongata; OB, olfactory bulb; OT, optic tectum; PG, preglomerular complex; PO, preoptic area;PrT, pretectum; PTd, posterior tuberculum dorsal part; PTh, prethalamus; PTv posterior tuberculum ventral part; Teg, tegmentum; Th, thalamus; TS, torus semicircularis; V, ventral telencephalon/subpallium; Va, valvula cerebelli.

Description

The pretectal region forms the dorsal most part of the diencephalon. The main sensory input to the pretectum is visual with axons from a subset of retinal ganglion cells branch off and arborise in arborisation fields in the pretectum on their way to innervate the optic tectum (Robles et al., 2014).

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Ontology
 

is part of: diencephalon

has parts: superficial pretectum, central pretectum, periventricular pretectal nucleus.

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ZFIN

OLS Tree Diagram

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Anatomical segmentation of 3 day old zebrafish larval brain by Thomas Müller, Olaf Ronneberger, Wolfgang Driever and colleagues. For details see Ronneberger et al., Nat. Meth. 2012 and http://vibez.informatik.uni-freiburg.de

Transgenic Lines that label this brain region

Antibodies that label this brain region

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Key Publications

Antinucci P, Folgueira M, Bianco IH.
Pretectal neurons control hunting behaviour.
eLife (2019) 8 doi.org/10.7554/eLife.48114

Estuardo Robles, Eva Laurell, and Herwig Baier (2014)
The Retinal Projectome Reveals Brain- Area-Specific Visual Representations Generated by Ganglion Cell Diversity.
Current Biology 24, 2085–2096.

Burrill, J.D., and Easter, S.S., Jr. (1994).
Development of the retinofugal projections in the embryonic and larval zebrafish (Brachydanio rerio).
J. Comp. Neurol. 346, 583–600.

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diencephalon

Forebrain > Diencephalon

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Description

The posterior neuromere of the forebrain that gives rise to the optic cups, epithalamus, thalamus,  ventral thalamus and hypothalmus.

“The diencephalon proper has five major divisions which, in the adult brain, appear in a dorsoventral arrangement. They are the epithalamus, dorsal thalamus, ventral thalamus, posterior tuberculum and hypothalamus. The preoptic area , although often considered part of the hypothalamus, constitutes an intermediate region between telencephalon and diencephalon.” (Wulliman et al., 1996).

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Ontology
 

is part of: forebrain

has parts: caudal tuberculum, diencephalic white matter, epithalamus, hypophysis, hypothalamus, optic stalk, preoptic area, pretectum, synencephalon, thalamus, third ventricle

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ZFIN

OLS Tree Diagram

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Transgenic Lines that label this brain region

Antibodies that label this brain region

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Key Publications

Wullimann, M.F., Rupp, B., Reichert, H., and eds. (1996)
Neuroanatomy of the Zebrafish Brain. A Topological Atlas.
Basel, Switzerland: Basel, Switzerland: Birkhäuser Verlag. :160 p.

Mueller, T., 2012. 
What is the thalamus in zebrafish?
Frontiers in Neuroscience,6. pp.1–14.

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