scholarly journals Msx1-Positive Progenitors in the Retinal Ciliary Margin Give Rise to Both Neural and Non-neural Progenies in Mammals

2017 ◽  
Vol 40 (2) ◽  
pp. 137-150 ◽  
Author(s):  
Marie-Claude Bélanger ◽  
Benoit Robert ◽  
Michel Cayouette
Keyword(s):  
Ciliary Margin

The Xenopus homologue of the Drosophila gene tailless has a function in early eye development

Development ◽  
1998 ◽  
Vol 125 (13) ◽  
pp. 2425-2432 ◽  
Author(s):  
T. Hollemann ◽  
E. Bellefroid ◽  
T. Pieler
Keyword(s):  
Eye Development ◽  
Neural Plate ◽  
Regulatory Function ◽  
Genetic Circuits ◽  
Optic Stalk ◽  
Drosophila Gene ◽  
Ciliary Margin ◽  
Evolutionarily Conserved ◽  
Optic Cup ◽  
Vertebrate Eye

Genetic circuits responsible for the development of photoreceptive organs appear to be evolutionarily conserved. Here, the Xenopus homologue Xtll of the Drosophila gene tailless (tll), which we find to be expressed during early eye development, is characterized with respect to its relationship to vertebrate regulators of eye morphogenesis, such as Pax6 and Rx. Expression of all three genes is first detected in the area corresponding to the eye anlagen within the open neural plate in partially overlapping, but not identical, patterns. During the evagination of the optic vesicle, Xtll expression is most prominent in the optic stalk, as well as in the distal tip of the forming vesicle. In tadpole-stage embryos, Xtll gene transcription is most prominent in the ciliary margin of the optic cup. Inhibition of Xtll function in Xenopus embryos interferes specifically with the evagination of the eye vesicle and, in consequence, Xpax6 gene expression is severely reduced in such manipulated embryos. These findings suggest that Xtll serves an important regulatory function in the earliest phases of vertebrate eye development.

Distribution of Müller stem cells within the neural retina: Evidence for the existence of a ciliary margin-like zone in the adult human eye

2009 ◽  
Vol 89 (3) ◽  
pp. 373-382 ◽  
Author(s):  
Bhairavi Bhatia ◽  
Shweta Singhal ◽  
Jean M. Lawrence ◽  
Peng T. Khaw ◽  
G. Astrid Limb
Keyword(s):  
Stem Cells ◽  
Neural Retina ◽  
Human Eye ◽  
Adult Human ◽  
Ciliary Margin

scholarly journals The Genetic Sequence of Retinal Development in the Ciliary Margin of theXenopusEye

1998 ◽  
Vol 199 (2) ◽  
pp. 185-200 ◽  
Author(s):  
Muriel Perron ◽  
Shami Kanekar ◽  
Monica L. Vetter ◽  
William A. Harris
Keyword(s):  
Retinal Development ◽  
Genetic Sequence ◽  
Ciliary Margin

The relationship between retinal and tectal growth in larval Xenopus: implications for the development of the retino-tectal projection

Development ◽  
1979 ◽  
Vol 53 (1) ◽  
pp. 103-143
Author(s):  
R. M. Gaze ◽  
M. J. Keating ◽  
A. Ostberg ◽  
S-H Chung
Keyword(s):  
Quantitative Analysis ◽  
Small Proportion ◽  
Developmental Stages ◽  
The Other ◽  
Larval Life ◽  
Ciliary Margin ◽  
Retinal Growth ◽  
Temporal Pole ◽  
Optic Axons ◽  
The Relationship

The modes of retinal and tectal histogenesis, as well as the patterns of terminal distribution of optic axons in larval Xenopus were studied, using anatomical techniques. We show that the retina grows by adding strips of cells at its ciliary margin. The pattern of retinal growth is asymmetrical along the dorso-ventral axis of the retina. On the other hand, the ectum grows by adding newly formed cells caudo-medially. The most rapid tectal growth takes place between stages 50 and 53, and thereafter only a small proportion of cells are added near the midline of the caudal tectum. Despite such incongruent modes of retinal and tectal growth, retinotopic order is maintained throughout larval life. We present here further evidence supporting the idea that connexions between the arrays of retinal and tectal cells shift progressively caudo-medially on the tectum during the period of growth. When the temporal pole of the retina is destroyed at various developmental stages, the density of degenerating synapses is always highest in the rostral pole of the tectum. Moreover, optic terminals stemming from the central retina spread caudally, invading newly maturing regions of the tectum. Quantitative analysis of the terminal distributions of optic axons suggest that orderly shifts in synaptic contacts between optic axons and tectal dendrites take place in the course of development. Ultrastructural observations on the maturing tectal neuropil are consistent with this view.

The fine structure of the developing retina in Xenopus laevis

Development ◽  
1972 ◽  
Vol 28 (3) ◽  
pp. 659-666
Author(s):  
J. S. Dixon ◽  
J. R. Cronly-Dillon
Keyword(s):  
Fine Structure ◽  
Xenopus Laevis ◽  
Retinal Cell ◽  
Optic Vesicle ◽  
Cell Specification ◽  
Ciliary Margin ◽  
Large Numbers ◽  
Outer Aspect ◽  
Cell To Cell Transfer ◽  
Pigment Epithelial Cells

The fine structure of the developing retinal cells in Xenopus laevis was studied from stages 26 to 36. At all stages examined the cells contained large numbers of free ribosomes, polysomes, small mitochondria, lipid and yolk droplets and scanty granular reticulum. A basal lamina covered the smooth internal margin of the optic vesicle and also the external aspect of the germinal pigment epithelial cells. At all stages examined zonulae adhaerentes occurred between adjacent cells at the outer aspect of the optic vesicle and maculae adhaerentes diminutae were occasionally observed. A third type of intercellular junction, characterized by a narrow gap of 3–9 nm, occurred throughout the retina up to stage 30 but only at the periphery beyond this stage. It is suggested that the disappearance of these junctions from the central portion of the retina may be correlated with retinal cell specification* which is known to occur at stage 30–31. These junctions may represent sites for the cell to cell transfer of small molecules which are required for cell differentiation. Since new cells are continually being added to the retina from the ciliary margin beyond stage 30 the persistence of junctions in this region may explain how these new cells also become specified.*

scholarly journals The Ciliary Margin Zone of the Mammalian Retina Generates Retinal Ganglion Cells

Cell Reports ◽  
2016 ◽  
Vol 17 (12) ◽  
pp. 3153-3164 ◽  
Author(s):  
Florencia Marcucci ◽  
Veronica Murcia-Belmonte ◽  
Qing Wang ◽  
Yaiza Coca ◽  
Susana Ferreiro-Galve ◽  
...  
Keyword(s):  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Retinal Ganglion ◽  
Ciliary Margin ◽  
Mammalian Retina

Cell lineage analysis reveals multipotent precursors in the ciliary margin of the frog retina

1989 ◽  
Vol 136 (1) ◽  
pp. 254-263 ◽  
Author(s):  
Richard Wetts ◽  
George N. Serbedzija ◽  
Scott E. Fraser
Keyword(s):  
Cell Lineage ◽  
Ciliary Margin ◽  
Frog Retina ◽  
Lineage Analysis
Sign in / Sign up

Export Citation Format

Share Document