HOP: Proteins and Enzymes

HOP, also known as Homeodomain-only protein, has a 73 amino acid short isoform that is 8 kDa and a long 94 amino acid isoform that is 10 kDa; nucleus located; widely expressed in the heart, brain, placenta, lung, skeletal and smooth muscles, uterus, urinary bladder, kidney and spleen; may interact with serum response factor (SRF) and modulate SRF-dependent cardiac-specific gene expression and cardiac development; prevents SRF-dependent transcription either by inhibiting SRF binding to DNA or by recruiting histone deacetylase (HDAC) proteins that prevent transcription by SRF; overexpression causes cardiac hypertrophy; and may also act as a tumor suppressor. Disease research is currently being studied with relation to choriocarcinoma, abdominal actinomycosis, nevus of ota, actinomycosis, lung cancer, nevus, carcinoma, squamous cell carcinoma, oral squamous cell carcinoma, esophageal squamous cell carcinoma, dilated cardiomyopathy, thyroid carcinoma, endometrial cancer, cardiomyopathy, gastric cancer, glioblastoma, esophagitis, and thyroiditis. This protein has shown an interaction with HDAC2, EPC1, SRF, GZMB, HOXB9, TLX3, and ZSCAN1 in the negative regulation of transcription from RNA polymerase II promoter, trophectodermal cell differentiation, transcription, DNA-dependent, regulation of transcription, DNA-dependent, and multicellular organismal development pathways.