visual system homeobox 1; homeodomain protein RINX; retinal inner nuclear layer homeobox protein; transcription factor VSX1 (VSX1, RINX)

Function

• binds to the 37-bp core of the locus control region (LCR) of the red/green visual pigment gene cluster
• may regulate activity of the LCR & the cone opsin genes at earlier stages of development

Structure

• belongs to the paired homeobox family
• contains 1 CVC domain
• contains 1 homeobox DNA-binding domain

Compartment

nucleus (putative)

Alternative splicing

• named isoforms=8
• additional isoforms seem to exist

Expression

• in the adult eye, expressed in lens, iris, ciliary body, choroid, optical nerve head &, most strongly, in retina
• not expressed in sclera & cornea. according to
• expressed in adult retina but not in lens & cornea
• within adult retina, found exclusively in the inner nuclear layer
• isoform 1, isoform 2, isoform 3 & isoform 4
  • expressed in adult retina
  • not expressed in brain, heart, kidney, liver, lung, pancreas, placenta & skeletal muscle
• not expressed in thymus & spleen
• expressed in embryonic craniofacial tissue
• expressed in fetal (week 14) retina
• strongly expressed in neonatal retina (day 0)
• weakly expressed in neonatal lens (day 0), choroid (day 0) & cornea (day 0, 4; month 9)

Pathology

• defects in VSX1 are a cause of
  • posterior polymorphous corneal dystrophy type 1
  • keratoconus

More general terms

• homeobox protein
• transcription factor (TF)

Additional terms

• posterior polymorphous corneal dystrophy

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=30813
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:30813
• OMIM: https://mirror.omim.org/entry/122000
• OMIM: https://mirror.omim.org/entry/148300
• OMIM: https://mirror.omim.org/entry/605020
• UniProt: http://www.uniprot.org/uniprot/Q9NZR4.html