homeobox protein SIX5; DM locus-associated homeodomain protein; sine oculis homeobox homolog 5 (SIX5, DMAHP)

Function

• transcription factor
• thought to be involved in regulation of organogenesis
• may be involved in determination & maintenance of retina
• binds a 5'-GGTGTCAG-3' motif present in the ARE regulatory element of ATP1A1
• binds a 5'-TCA[AG][AG]TTNC-3' motif present in the MEF3 element in the myogenin promoter, & in the IGFBP5 promoter (putative)
• hought to be regulated by association with Dach & Eya proteins, & seems to be coactivated by EYA1, EYA2 & EYA3
• probably binds dsDNA
• interacts with EYA3, & probably EYA1 & EYA2

Structure

• belongs to the SIX/sine oculis homeobox family
• contains 1 homeobox DNA-binding domain

Compartment

cytoplasm, nucleus

Alternative splicing

named isoforms=2

Expression

• expressed in adult eyes
• not expressed in fetal eyes
• found in corneal epithelium & endothelium, lens epithelium, ciliary body epithelia, cellular layers of the retina & the sclera
• at the begin of fourth week of development, detected in cytoplasm of somite cells
• at the end of fourth week is accumulated in the nucleus of somite cells
• Between the sixth & eighth week of development detected in the nucleus of limb bud cells

Pathology

• defects in SIX5 are the cause of branchiootorenal syndrome type 2

More general terms

• homeobox protein SIX; sine oculis homeobox homolog (SIX)

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=147912
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:147912
• OMIM: https://mirror.omim.org/entry/600963
• OMIM: https://mirror.omim.org/entry/610896
• UniProt: http://www.uniprot.org/uniprot/Q8N196.html