eyes absent homolog 2 (EYA2, EAB1)

Function

• tyrosine phosphatase
• specifically dephosphorylates Tyr-142 of histone H2AX
• Tyr-142 phosphorylation of histone H2AX plays a central role in DNA repair & acts as a mark that distinguishes between apoptotic & repair responses to genotoxic stress
• promotes efficient DNA repair by dephosphorylating H2AX, promoting the recruitment of DNA repair complexes containing MDC1
• its function as histone phosphatase probably explains its role in transcription regulation during organogenesis
• coactivates SIX1
• seems to coactivate SIX2, SIX4 & SIX5
• together with SIX1 & DACH2 seem to be involved in myogenesis
• may be involved in development of the eye
• interaction with GNAZ & GNAI2 prevents nuclear translocation & transcriptional activity
• interacts with GNAZ & GNAI2
• interacts with DACH2 & SIX1, & probably with SIX2, SIX4 & SIX5
• interacts with CAPN8

Cofactor: binds 1 Mg+2 ion per subunit

Kinetic parameters:

• KM=1.9 uM for H2AX-Y142-phosphate
• KM=80 uM for H2AX-S139-phosphate

Structure

• belongs to the HAD-like hydrolase superfamily, EYA family

Compartment

• cytoplasm (putative)
• nucleus

Alternative splicing

named isoforms=3

Expression

• highest expression in muscle with lower levels in kidney, placenta, pancreas, brain & heart
• at the begin of fourth week of development, detected in cytoplasm of somite cells
• between the 6th & 8th week of development, detected in cytoplasm of limb bud cells

More general terms

• eyes absent homolog
• phosphoprotein
• tyrosine phosphatase (protein tyrosine phosphatate, PTP)

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=2139
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:2139
• OMIM: https://mirror.omim.org/entry/601654
• UniProt: http://www.uniprot.org/uniprot/O00167.html