Molecular cloning, genomic structure, and protein characterization of mouse optineurin

We recently identified optineurin (OPTN) as a novel gene for glaucoma and determined its mRNA and protein expression patterns in different human tissues. Herein, we describe the cloning, mapping, genomic organization, and mRNA and protein expression patterns for murine optineurin (Optn). We mapped Optn to chromosome 2, within a region that is syntenic to human 10p14. Optn has 13 coding exons and its exon-intron boundaries are evolutionarily conserved with human. Optn encodes an 884-amino-acid protein and shows 78% identity to OPTN. Northern blot analysis revealed three mRNA transcripts with highest expression in adult liver, heart, and testis and with earliest detectable message in 7-day-old embryos. In situ hybridization showed prominent ocular expression during mouse embryonic development. Optn colocalizes with vesicular structures near the nucleus and is expressed in anterior segment, retina, and optic nerve blood vessels. Gene and protein ocular profiling of Optn is a prerequisite for developing a mouse model for glaucoma.