Two transcription factors, Pou4f2 and Isl1, are sufficient to specify the retinal ganglion cell fate

As with other retinal cell types, retinal ganglion cells (RGCs) arise from multipotent retinal progenitor cells (RPCs), and their formation is regulated by a hierarchical gene-regulatory network (GRN). Within this GRN, three transcription factors—atonal homolog 7 (Atoh7), POU domain, class 4, transcription factor 2 (Pou4f2), and insulin gene enhancer protein 1 (Isl1)—occupy key node positions at two different stages of RGC development. Atoh7 is upstream and is required for RPCs to gain competence for an RGC fate, whereas Pou4f2 and Isl1 are downstream and regulate RGC differentiation. However, the genetic and molecular basis for the specification of the RGC fate, a key step in RGC development, remains unclear. Here we report that ectopic expression of Pou4f2 and Isl1 in the Atoh7-null retina using a binary knockin-transgenic system is sufficient for the specification of the RGC fate. The RGCs thus formed are largely normal in gene expression, survive to postnatal stages, and are physiologically functional. Our results indicate that Pou4f2 and Isl1 compose a minimally sufficient regulatory core for the RGC fate. We further conclude that during development a core group of limited transcription factors, including Pou4f2 and Isl1, function downstream of Atoh7 to determine the RGC fate and initiate RGC differentiation.

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Development of cholinergic amacrine cell stratification in the ferret retina and the effects of early excitotoxic ablation

Visual Neuroscience ◽

10.1017/s0952523801184063 ◽

2001 ◽

Vol 18 (4) ◽

pp. 559-570 ◽

Cited By ~ 20

Author(s):

B.E. REESE ◽

M.A. RAVEN ◽

K.A. GIANNOTTI ◽

P.T. JOHNSON

Keyword(s):

Ganglion Cell ◽

Ganglion Cells ◽

Plexiform Layer ◽

Amacrine Cells ◽

Cell Types ◽

Retinal Cell ◽

Inner Plexiform Layer ◽

Retinal Ganglion ◽

Outer Border ◽

Cholinergic Amacrine Cells

The present study has examined the emergence of cholinergic stratification within the developing inner plexiform layer (IPL), and the effect of ablating the cholinergic amacrine cells on the formation of other stratifications within the IPL. The population of cholinergic amacrine cells in the ferret's retina was identified as early as the day of birth, but their processes did not form discrete strata until the end of the first postnatal week. As development proceeded over the next five postnatal weeks, so the positioning of the cholinergic strata shifted within the IPL toward the outer border, indicative of the greater ingrowth and elaboration of processes within the innermost parts of the IPL. To examine whether these cholinergic strata play an instructive role upon the development of other stratifications which form within the IPL, one-week-old ferrets were treated with l-glutamate in an attempt to ablate the population of cholinergic amacrine cells. Such treatment was shown to be successful, eliminating all of the cholinergic amacrine cells as well as the alpha retinal ganglion cells in the central retina. The remaining ganglion cell classes as well as a few other retinal cell types were partially reduced, while other cell types were not affected, and neither retinal histology nor areal growth was compromised in these ferrets. Despite this early loss of the cholinergic amacrine cells, which are eliminated within 24 h, other stratifications within the IPL formed normally, as they do following early elimination of the entire ganglion cell population. While these cholinergic amacrine cells are present well before other cell types have differentiated, apparently neither they, nor the ganglion cells, play a role in determining the depth of stratification for other retinal cell types.

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Ganglion cells influence the fate of dividing retinal cells in culture

Development ◽

10.1242/dev.125.6.1059 ◽

1998 ◽

Vol 125 (6) ◽

pp. 1059-1066 ◽

Cited By ~ 6

Author(s):

D.K. Waid ◽

S.C. McLoon

Keyword(s):

Ganglion Cell ◽

Cell Fate ◽

Cell Population ◽

Antisense Oligonucleotide ◽

Ganglion Cells ◽

Cell Types ◽

Retinal Cell ◽

Retinal Cells ◽

Cell Production ◽

Cellular Environment

The different retinal cell types arise during vertebrate development from a common pool of progenitor cells. The mechanisms responsible for determining the fate of individual retinal cells are, as yet, poorly understood. Ganglion cells are one of the first cell types to be produced in the developing vertebrate retina and few ganglion cells are produced late in development. It is possible that, as the retina matures, the cellular environment changes such that it is not conducive to ganglion cell determination. The present study showed that older retinal cells secrete a factor that inhibits the production of ganglion cells. This was shown by culturing younger retinal cells, the test population, adjacent to various ages of older retinal cells. Increasingly older retinal cells, up to embryonic day 9, were more effective at inhibiting production of ganglion cells in the test cell population. Ganglion cell production was restored when ganglion cells were depleted from the older cell population. This suggests that ganglion cells secrete a factor that actively prevents cells from choosing the ganglion cell fate. This factor appeared to be active in medium conditioned by older retinal cells. Analysis of the conditioned medium established that the factor was heat stable and was present in the <3 kDa and >10 kDa fractions. Previous work showed that the neurogenic protein, Notch, might also be active in blocking production of ganglion cells. The present study showed that decreasing Notch expression with an antisense oligonucleotide increased the number of ganglion cells produced in a population of young retinal cells. Ganglion cell production, however, was still inhibited in cultures using antisense oligonucleotide to Notch in medium conditioned by older retinal cells. This suggests that the factor secreted by older retinal cells inhibits ganglion cell production through a different pathway than that mediated by Notch.

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An alternative approach to produce versatile retinal organoids with accelerated ganglion cell development

Scientific Reports ◽

10.1038/s41598-020-79651-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Philip E. Wagstaff ◽

Anneloor L. M. A. ten Asbroek ◽

Jacoline B. ten Brink ◽

Nomdo M. Jansonius ◽

Arthur A. B. Bergen

Keyword(s):

Ganglion Cells ◽

Cell Types ◽

Retinal Cell ◽

Specific Cell ◽

Retinal Ganglion ◽

In Vivo Models ◽

Alternative Approach

AbstractGenetically complex ocular neuropathies, such as glaucoma, are a major cause of visual impairment worldwide. There is a growing need to generate suitable human representative in vitro and in vivo models, as there is no effective treatment available once damage has occured. Retinal organoids are increasingly being used for experimental gene therapy, stem cell replacement therapy and small molecule therapy. There are multiple protocols for the development of retinal organoids available, however, one potential drawback of the current methods is that the organoids can take between 6 weeks and 12 months on average to develop and mature, depending on the specific cell type wanted. Here, we describe and characterise a protocol focused on the generation of retinal ganglion cells within an accelerated four week timeframe without any external small molecules or growth factors. Subsequent long term cultures yield fully differentiated organoids displaying all major retinal cell types. RPE, Horizontal, Amacrine and Photoreceptors cells were generated using external factors to maintain lamination.

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Math5 is required for retinal ganglion cell and optic nerve formation

Development ◽

10.1242/dev.128.13.2497 ◽

2001 ◽

Vol 128 (13) ◽

pp. 2497-2508 ◽

Cited By ~ 12

Author(s):

Nadean L. Brown ◽

Sima Patel ◽

Joseph Brzezinski ◽

Tom Glaser

Keyword(s):

Optic Nerve ◽

Cell Fate ◽

Ganglion Cells ◽

Cell Types ◽

Visual Signals ◽

Bhlh Transcription Factor ◽

Retinal Ganglion ◽

Retinal Neuron ◽

Extrinsic Factors ◽

Helix Loop Helix

The vertebrate retina contains seven major neuronal and glial cell types in an interconnected network that collects, processes and sends visual signals through the optic nerve to the brain. Retinal neuron differentiation is thought to require both intrinsic and extrinsic factors, yet few intrinsic gene products have been identified that direct this process. Math5 (Atoh7) encodes a basic helix-loop-helix (bHLH) transcription factor that is specifically expressed by mouse retinal progenitors. Math5 is highly homologous to atonal, which is critically required for R8 neuron formation during Drosophila eye development. Like R8 cells in the fly eye, retinal ganglion cells (RGCs) are the first neurons in the vertebrate eye. Here we show that Math5 mutant mice are fully viable, yet lack RGCs and optic nerves. Thus, two evolutionarily diverse eye types require atonal gene family function for the earliest stages of retinal neuron formation. At the same time, the abundance of cone photoreceptors is significantly increased in Math5−/− retinae, suggesting a binary change in cell fate from RGCs to cones. A small number of nascent RGCs are detected during embryogenesis, but these fail to develop further, suggesting that committed RGCs may also require Math5 function.

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ANANSE: An enhancer network-based computational approach for predicting key transcription factors in cell fate determination

10.1101/2020.06.05.135798 ◽

2020 ◽

Author(s):

Quan Xu ◽

Georgios Georgiou ◽

Gert Jan C. Veenstra ◽

Huiqing Zhou ◽

Simon J. van Heeringen

Keyword(s):

Transcription Factors ◽

Cell Fate ◽

Gene Regulatory Networks ◽

Regulatory Networks ◽

Cell Types ◽

Cell Fate Determination ◽

Cell Type ◽

Fate Determination ◽

Cell Type Specific ◽

Gene Regulatory

AbstractProper cell fate determination is largely orchestrated by complex gene regulatory networks centered around transcription factors. However, experimental elucidation of key transcription factors that drive cellular identity is currently often intractable. Here, we present ANANSE (ANalysis Algorithm for Networks Specified by Enhancers), a network-based method that exploits enhancer-encoded regulatory information to identify the key transcription factors in cell fate determination. As cell type-specific transcription factors predominantly bind to enhancers, we use regulatory networks based on enhancer properties to prioritize transcription factors. First, we predict genome-wide binding profiles of transcription factors in various cell types using enhancer activity and transcription factor binding motifs. Subsequently, applying these inferred binding profiles, we construct cell type-specific gene regulatory networks, and then predict key transcription factors controlling cell fate conversions using differential gene networks between cell types. This method outperforms existing approaches in correctly predicting major transcription factors previously identified to be sufficient for trans-differentiation. Finally, we apply ANANSE to define an atlas of key transcription factors in 18 normal human tissues. In conclusion, we present a ready-to-implement computational tool for efficient prediction of transcription factors in cell fate determination and to study transcription factor-mediated regulatory mechanisms. ANANSE is freely available at https://github.com/vanheeringen-lab/ANANSE.

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Mammalian Retinal Cell Quantification

Toxicologic Pathology ◽

10.1177/0192623320976375 ◽

2020 ◽

pp. 019262332097637

Author(s):

Anantharaman Muthuswamy ◽

Henry Chen ◽

Ying Hu ◽

Oliver C. Turner ◽

Olulanu H. Aina

Keyword(s):

Vision Loss ◽

Ganglion Cells ◽

Cell Types ◽

Age Related Macular Degeneration ◽

Retinal Cell ◽

Retinal Diseases ◽

Retinal Ganglion ◽

Retinal Cells ◽

Cell Quantification ◽

Age Related

Normal retina and its cell layers are essential for processing visual stimuli, and loss of its integrity has been documented in many disease processes. The numbers and the axonal processes of retinal ganglion cells are reduced substantially in glaucoma, leading to vision loss and blindness. Similarly, selective loss of photoreceptors in age-related macular degeneration and hereditary retinal dystrophies also results in the compromise of visual acuity. Development of genetically modified mice has led to increased understanding of the pathogenesis of many retinal diseases. Similarly, in this digital era, usage of modalities to quantify the retinal cell loss has grown exponentially leading to a better understanding of the suitability of animal models to study human retinal diseases. These quantification modalities provide valuable quantifiable data in studying pathogenesis and disease progression. This review will discuss the immunohistochemical markers for various retinal cells, available automated tools to quantify retinal cells, and present an example of retinal ganglion cell quantification using HALO image analysis platform. Additionally, we briefly review retinal cell types and subtypes, salient features of retina in various laboratory animal species, and a few of the main disease processes that affect retinal cell numbers in humans.

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Neurogenesis and Specification of Retinal Ganglion Cells

International Journal of Molecular Sciences ◽

10.3390/ijms21020451 ◽

2020 ◽

Vol 21 (2) ◽

pp. 451 ◽

Cited By ~ 4

Author(s):

Kim Tuyen Nguyen-Ba-Charvet ◽

Alexandra Rebsam

Keyword(s):

Retinal Ganglion Cells ◽

Molecular Mechanisms ◽

Ganglion Cells ◽

Cell Types ◽

Retinal Cell ◽

Retinal Ganglion ◽

Intrinsic Factors ◽

Visual Deficits ◽

Retinal Neurogenesis ◽

Cell Niche

Across all species, retinal ganglion cells (RGCs) are the first retinal neurons generated during development, followed by the other retinal cell types. How are retinal progenitor cells (RPCs) able to produce these cell types in a specific and timely order? Here, we will review the different models of retinal neurogenesis proposed over the last decades as well as the extrinsic and intrinsic factors controlling it. We will then focus on the molecular mechanisms, especially the cascade of transcription factors that regulate, more specifically, RGC fate. We will also comment on the recent discovery that the ciliary marginal zone is a new stem cell niche in mice contributing to retinal neurogenesis, especially to the generation of ipsilateral RGCs. Furthermore, RGCs are composed of many different subtypes that are anatomically, physiologically, functionally, and molecularly defined. We will summarize the different classifications of RGC subtypes and will recapitulate the specification of some of them and describe how a genetic disease such as albinism affects neurogenesis, resulting in profound visual deficits.

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Retinal self-organization: a model of RGC and SAC mosaic formation

10.1101/2021.10.22.465398 ◽

2021 ◽

Author(s):

Jean de Montigny ◽

Evelyne Sernagor ◽

Roman Bauer

Keyword(s):

Visual Information ◽

Ganglion Cells ◽

Amacrine Cells ◽

Cell Types ◽

Retinal Cell ◽

Retinal Ganglion ◽

Uniform Sampling ◽

Tangential Migration ◽

Starburst Amacrine Cells

Individual retinal cell types exhibit semi-regular spatial patterns called retinal mosaics. These mosaics enable uniform sampling of visual information and are formed to varying degrees across cell types. Retinal ganglion cells (RGC) and amacrine cells (including starburst amacrine cells (SAC)) are notably known to exhibit such layouts. Mechanisms responsible for the formation of such organised structures and their requirements are still not well understood. Mosaic formation follows three main principles: (1) homotypic cells prevent nearby cells from adopting the same type, (2) cell tangential migration, with homotypic cell repulsion, (3) cell death (with RGCs exhibiting high rates of apoptosis).

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Spatial receptive field properties of rat retinal ganglion cells

Visual Neuroscience ◽

10.1017/s0952523811000307 ◽

2011 ◽

Vol 28 (5) ◽

pp. 403-417 ◽

Cited By ~ 19

Author(s):

WALTER F. HEINE ◽

CHRISTOPHER L. PASSAGLIA

Keyword(s):

Receptive Field ◽

Ganglion Cell ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Cell Types ◽

Quantitative Information ◽

Retinal Ganglion ◽

X And Y Cells ◽

Y Cells

AbstractThe rat is a popular animal model for vision research, yet there is little quantitative information about the physiological properties of the cells that provide its brain with visual input, the retinal ganglion cells. It is not clear whether rats even possess the full complement of ganglion cell types found in other mammals. Since such information is important for evaluating rodent models of visual disease and elucidating the function of homologous and heterologous cells in different animals, we recorded from rat ganglion cells in vivo and systematically measured their spatial receptive field (RF) properties using spot, annulus, and grating patterns. Most of the recorded cells bore likeness to cat X and Y cells, exhibiting brisk responses, center-surround RFs, and linear or nonlinear spatial summation. The others resembled various types of mammalian W cell, including local-edge-detector cells, suppressed-by-contrast cells, and an unusual type with an ON–OFF surround. They generally exhibited sluggish responses, larger RFs, and lower responsiveness. The peak responsivity of brisk-nonlinear (Y-type) cells was around twice that of brisk-linear (X-type) cells and several fold that of sluggish cells. The RF size of brisk-linear and brisk-nonlinear cells was indistinguishable, with average center and surround diameters of 5.6 ± 1.3 and 26.4 ± 11.3 deg, respectively. In contrast, the center diameter of recorded sluggish cells averaged 12.8 ± 7.9 deg. The homogeneous RF size of rat brisk cells is unlike that of cat X and Y cells, and its implication regarding the putative roles of these two ganglion cell types in visual signaling is discussed.

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A mini review on production of pluripotency factors (Oct4, Sox2, Klf4 and c-Myc) through recombinant protein technology

Communications in Science and Technology ◽

10.21924/cst.5.1.2020.171 ◽

2020 ◽

Vol 5 (1) ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

David Septian Sumanto Marpaung ◽

Ayu Oshin Yap Sinaga

Keyword(s):

Stem Cells ◽

Transcription Factors ◽

Embryonic Stem Cells ◽

Pluripotent Stem Cells ◽

Ectopic Expression ◽

Embryonic Stem ◽

Cell Types ◽

Induced Pluripotency ◽

Pluripotency Factors ◽

Induced Pluripotent

The four transcription factors OCT4, SOX2, KLF4 and c-MYC are highly expressed in embryonic stem cells (ESC) and their overexpression can induce pluripotency, the ability to differentiate into all cell types of an organism. The ectopic expression such transcription factors could reprogram somatic stem cells become induced pluripotency stem cells (iPSC), an embryonic stem cells-like. Production of recombinant pluripotency factors gain interests due to high demand from generation of induced pluripotent stem cells in regenerative medical therapy recently. This review will focus on demonstrate the recent advances in recombinant pluripotency factor production using various host.

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