Retinal bipolar cells are interneurons that transmit visual signals from photoreceptors to ganglion cells. Although the visual pathways mediated by bipolar cells have been well characterized, the genes that regulate their development and function are largely unknown. To determine the role in bipolar cell development of the homeobox gene Vsx1, whose retinal expression is restricted to a major su...

PURPOSE To characterize the expression of the visual system homeobox gene (VSX1) in human corneal keratocytes both in vitro and in vivo. METHODS The expression of VSX1 was evaluated through semiquantitative RT-PCR, immunofluorescence and in situ hybridization both in corneas (either freshly obtained or wounded) and in collagenase/hyaluronidase-isolated keratocytes grown in the absence or pres...

CHX10 and VSX1 are homeodomain (HD) proteins essential for normal retinal development. CHX10 is required first for retinal progenitor cell proliferation and later for bipolar cell differentiation, whereas VSX1 is important in the terminal differentiation of a subset of bipolar cells. Elucidating the transcriptional activity of CHX10 and VSX1 is required to understand how these factors control r...

The paired-like homeodomain (HD) protein Chx10 is distinguished by the presence of the CVC domain, a conserved 56 amino acid sequence C-terminal to the HD. In mammals, Chx10 is essential both for the proliferation of retinal progenitor cells and for the formation or survival of retinal bipolar interneurons. We describe the cloning and characterization of a mouse Chx10 homologue, Vsx1; phylogene...

The paired-like homeodomain (HD) protein Chx10 is distinguished by the presence of the CVC domain, a conserved 56 amino acid sequence C-terminal to the HD. In mammals, Chx10 is essential both for the proliferation of retinal progenitor cells and for the formation or survival of retinal bipolar interneurons. We describe the cloning and characterization of a mouse Chx10 homologue, Vsx1; phylogene...

PURPOSE To investigate mutations of visual system homeobox 1 (VSX1) and superoxide dismutase 1 (SOD1) in 20 patients with keratoconus in the south of Iran. METHODS Twenty patients with keratoconus who had a positive familial history were enrolled in this study and gave informed consent for DNA analysis. Genomic DNA was extracted from peripheral blood lymphocytes. Polymerase chain reaction (PC...

Spinal ventral interneurons regulate the activity of motor neurons, thereby controlling motor activities. Interneurons arise during embryonic development from distinct progenitor domains distributed orderly along the dorso-ventral axis of the neural tube. A single ventral progenitor population named p2 generates at least five V2 interneuron subsets. Whether the diversification of V2 precursors ...

PURPOSE To screen the visual system homebox 1 (VSX1) gene in Saudi Arabian keratoconus patients. METHODS We sequenced the entire coding region, exon-intron boundaries in clinically confirmed keratoconus patients (n=55) and 50 ethnically matched healthy controls. All cases and controls were unrelated. RESULTS Sequencing VSX1 revealed the presence of five nucleotide changes, 3 of which were n...

PURPOSE To determine whether mutations of the VSX1 gene play a pathogenetic role in the development of keratoconus (KTCN). METHODS DNA extraction, PCR amplification, and direct sequencing of the VSX1 gene were performed in 100 unrelated patients with diagnoses of clinical and topographic features of KTCN. RESULTS Of the four previously identified presumed pathogenic mutations in the VSX1 ge...

PURPOSE Proper visual transmission depends on the retinal ON and OFF pathways. We used Vsx1-/- mice with a retinal OFF visual pathway defect to determine the role of OFF pathway signaling in refractive development (RD) of the eye. METHODS Refractive development was measured every 2 weeks in Vsx1-/-, Vsx1+/+ (both on 129S1/Sv background), and commonly used C57BL/6J mice from 4 to 12 weeks of a...