Chromatin remodeling complexes are required for many distinct nuclear processes such as transcription, DNA replication, and DNA repair. However, the contribution of these complexes to the development of complex tissues within an organism is poorly characterized. Imitation switch (ISWI) proteins are among the most evolutionarily conserved ATP-dependent chromatin remodeling factors and are represented by yeast Isw1/Isw2, and their vertebrate counterparts Snf2h (Smarca5) and Snf2l (Smarca1). In this study, we focused on the role of the Snf2h gene during the development of the mammalian retina. We show that Snf2h is expressed in both retinal progenitors and post-mitotic retinal cells. Using Snf2h conditional knockout mice (Snf2h cKO), we found that when Snf2h is deleted, the laminar structure of the adult retina is not retained, the overall thickness of the retina is significantly reduced compared with controls, and the outer nuclear layer (ONL) is completely missing. The depletion of Snf2h did not influence the ability of retinal progenitors to generate all the differentiated retinal cell types. Instead, the Snf2h function is critical for the proliferation of retinal progenitor cells. Cells lacking Snf2h have a defective S-phase, leading to the entire cell division process impairments. Although all retinal cell types appear to be specified in the absence of the Snf2h function, cell-cycle defects and concomitantly increased apoptosis in Snf2h cKO result in abnormal retina lamination, complete destruction of the photoreceptor layer, and consequently, a physiologically non-functional retina.

• MeSH
• adenosintrifosfatasy * metabolismus   MeSH
• buněčné jádro metabolismus   MeSH
• chromatin * metabolismus   MeSH
• chromozomální proteiny, nehistonové * metabolismus   MeSH
• myši knockoutované MeSH
• myši MeSH
• proliferace buněk MeSH
• restrukturace chromatinu * MeSH
• retina MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

The vertebrate eye is derived from the neuroepithelium, surface ectoderm, and extracellular mesenchyme. The neuroepithelium forms an optic cup in which the spatial separation of three domains is established, namely, the region of multipotent retinal progenitor cells (RPCs), the ciliary margin zone (CMZ)-which possesses both a neurogenic and nonneurogenic potential-and the optic disk (OD), the interface between the optic stalk and the neuroretina. Here, we show by genetic ablation in the developing optic cup that Meis1 and Meis2 homeobox genes function redundantly to maintain the retinal progenitor pool while they simultaneously suppress the expression of genes characteristic of CMZ and OD fates. Furthermore, we demonstrate that Meis transcription factors bind regulatory regions of RPC-, CMZ-, and OD-specific genes, thus providing a mechanistic insight into the Meis-dependent gene regulatory network. Our work uncovers the essential role of Meis1 and Meis2 as regulators of cell fate competence, which organize spatial territories in the vertebrate eye.

• MeSH
• buněčná diferenciace genetika   MeSH
• genový knockdown MeSH
• homeodoménové proteiny genetika   metabolismus   MeSH
• kmenové buňky cytologie   metabolismus   MeSH
• obratlovci MeSH
• retina cytologie   metabolismus   MeSH
• transkripční faktory genetika   metabolismus   MeSH
• vývojová regulace genové exprese MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Conditional gene targeting in mice by means of Cre-loxP strategy represents a powerful approach to study mammalian gene function. This approach is however dependent on the availability of suitable strains of mice with a tissue or time restricted activity of the Cre recombinase. Here we describe Aldh3-Cre transgenic mice as a useful tool to conditionally delete genes in cornea, a specialized transparent tissue found on the anterior-most part of the eye, which acts as a protective barrier and contributes to the refractive power. Using a set of floxed alleles we demonstrate high Aldh3-Cre activity in corneal epithelial cells, corneal stroma and conjunctival epithelial cells at postnatal stages. Aldh3-Cre will thus be particularly beneficial for functional analysis of genes which are vital for postnatal development of cornea and conjunctiva.

• MeSH
• aldehyddehydrogenasa genetika   MeSH
• alely MeSH
• delece genu MeSH
• epitelové buňky fyziologie   MeSH
• genový targeting metody   MeSH
• integrasy genetika   MeSH
• konjunktiva fyziologie   MeSH
• myši transgenní genetika   fyziologie   MeSH
• myši MeSH
• rohovka fyziologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH