Modifying PCDH19 levels affects cortical interneuron migration.

PCDH19 is a transmembrane protein and member of the protocadherin family. It is encoded by the X-chromosome and more than 200 mutations have been linked to the neurodevelopmental PCDH-clustering epilepsy (PCDH19-CE) syndrome. A disturbed cell-cell contact that arises when random X-inactivation creates mosaic absence of PCDH19 has been proposed to cause the syndrome.

Subtle Roles of Down Syndrome Cell Adhesion Molecules in Embryonic Forebrain Development and Neuronal Migration.

Down Syndrome (DS) Cell Adhesion Molecules (DSCAMs) are transmembrane proteins of the immunoglobulin superfamily. Human DSCAM is located within the DS critical region of chromosome 21 (duplicated in Down Syndrome patients), and mutations or copy-number variations of this gene have also been associated to Fragile X syndrome, intellectual disability, autism, and bipolar disorder. The DSCAM paralogue DSCAM-like 1 (DSCAML1) maps to chromosome 11q23, implicated in the development of Jacobsen and Tourette syndromes.

Tightening the retinal glia limitans attenuates neuroinflammation after optic nerve injury.

Increasing evidence suggests that functional impairments at the level of the neurovascular unit (NVU) underlie many neurodegenerative and neuroinflammatory diseases. While being part of the NVU, astrocytes have been largely overlooked in this context and only recently, tightening of the glia limitans has been put forward as an important neuroprotective response to limit these injurious processes. In this study, using the retina as a central nervous system (CNS) model organ, we investigated the structure and function of the glia limitans, and reveal that the blood-retina barrier and glia limitans function as a coordinated double barrier to limit infiltration of leukocytes and immune molecules.

Extensive growth is followed by neurodegenerative pathology in the continuously expanding adult zebrafish retina.

The development of effective treatments for age-related neurodegenerative diseases remains one of the biggest medical challenges today, underscoring the high need for suitable animal model systems to improve our understanding of aging and age-associated neuropathology. Zebrafish have become an indispensable complementary model organism in gerontology research, yet their growth-control properties significantly differ from those in mammals. Here, we took advantage of the clearly defined and highly conserved structure of the fish retina to study the relationship between the processes of growth and aging in the adult zebrafish central nervous system (CNS).

Aberrant Collagen Composition of the Trabecular Meshwork Results in Reduced Aqueous Humor Drainage and Elevated IOP in MMP-9 Null Mice.

Purpose: Homeostatic turnover of the trabecular meshwork extracellular matrix (ECM) is essential to regulate aqueous humor outflow and to maintain intraocular pressure homeostasis. In this study, we evaluated aqueous humor turnover, intraocular pressure, and trabecular meshwork organization in MMP-9 null mice.

Methods: Intraocular pressure and aqueous humor turnover were measured in MMP-9 null versus wild-type mice.