High impact information on Vsx1

• Bipolar cell fate was not altered in the absence of Vsx1 function, because the pan-bipolar markers Chx10 and Ret-B1 continued to be expressed in inner nuclear layer neurons labeled by the Vsx1-targeting reporter gene, tauLacZ [1].
• To determine the role in bipolar cell development of the homeobox gene Vsx1, whose retinal expression is restricted to a major subset of differentiating and mature cone bipolar (CB) cells, we targeted the gene in mice [1].
• Control of late off-center cone bipolar cell differentiation and visual signaling by the homeobox gene Vsx1 [1].
• Electrophysiological studies demonstrated that Vsx1 mutant mice have defects in their cone visual pathway, whereas the rod visual pathway was unaffected [2].
• To determine the function of VSX1, we generated Vsx1 mutant mice and found that Vsx1 mutant retinal cells form but do not differentiate a mature cone bipolar cell phenotype [2].

Biological context of Vsx1

• Isolation and characterization of Vsx1, a novel mouse CVC paired-like homeobox gene expressed during embryogenesis and in the retina [3].
• Linkage analysis showed that mouse Vsx1 mapped to the distal region of chromosome 2 [3].

Anatomical context of Vsx1

• Analysis of the eyes of mouse chimeras generated with embryonic stem cells in which a lacZ reporter was targeted to the Vsx1 locus suggested that Vsx1 is expressed in the inner nuclear layer of the retina [3].
• We draw a parallel between the bipolar cells of the inner nuclear layer of the vertebrate retina, which express Chx10 and Vsx-1, and an interneuron in C. elegans called AIY, which expresses ceh-10 [4].

Other interactions of Vsx1

• Whereas Chx10 is expressed both in retinal progenitors in the developing eye and apparently in all bipolar cells of the mature retina, Vsx1 expression is first detected in the eye at postnatal day 5, where it is restricted to cone bipolar cells [5].
• These results indicate that there are at least two distinct genetic pathways (Irx5-dependent and Vsx1-dependent) regulating the development of Type 2 and Type 3 cone bipolar cells [6].

Analytical, diagnostic and therapeutic context of Vsx1

• RT-PCR analysis detected mouse Vsx1 transcripts from gastrulation and post-gastrulation stage mouse embryos, suggesting a role for Vsx1 during mouse embryogenesis [3].
• To analyze the possible roles for Vsx-1 and Vsx-2 in eye development, we used in situ hybridization to examine their expression patterns in zebrafish and goldfish embryos [7].

References