homeodomain-only protein; lung cancer-associated Y protein; odd homeobox protein 1; not expressed in choriocarcinoma protein 1 (HOP, HOPX, HOD, LAGY, NECC1, OB1)

Function

• atypical homeodomain protein
• does NOT bind DNA
• modulates cardiac growth & development
• acts via interaction with SRF
• modulates expression of SRF-dependent cardiac-specific genes
• prevents SRF-dependent transcription either by inhibiting SRF binding to DNA or by recruiting histone deacetylase
• may act as a tumor suppressor.
• component of large complex containing histone deacetylase(s) i.e. HDAC2

Compartment

nucleus

Alternative splicing

named isoforms=2

Expression

• widely expressed
• expressed in heart, brain, placenta, lung, skeletal muscle, smooth muscle, uterus, urinary bladder, kidney, spleen

Pathology

• defects in HOP may be a cause of cancer,
  • lung cancer, choriocarcinoma, head & neck cancer, oral squamous cell carcinoma
• overexpression causes cardiac hypertrophy

More general terms

• nuclear protein

Database

• OMIM: https://mirror.omim.org/entry/607275
• UniProt: http://www.uniprot.org/uniprot/Q9BPY8.html