Heterochromatin protein 1-binding protein 3 (HP1BP3)

Heterochromatin protein 1-binding protein 3 (HP1BP3) is a ubiquitously expressed nuclear protein in vertebrates. Structurally, it is evolutionarily related to the linker histone H1, containing three globular DNA-binding domains and a highly basic C-terminal region that promote chromatin compaction[1][2]. HP1BP3 specifically binds heterochromatin protein 1 (HP1) through a conserved HP1-binding motif and is enriched in heterochromatic regions of the nucleus. Functionally, HP1BP3 plays non-redundant roles in maintaining chromatin architecture, regulating gene expression, and advancing cell cycle progression by sustaining heterochromatin integrity. Additionally, it is involved in primary microRNA processing via association with the microprocessor complex[2]. Loss of HP1BP3 disrupts gene expression and leads to fatal developmental defects and chronic growth retardation, underscoring its essential functions for vertebrate survival and growth[1]. There are currently no drugs, established mechanisms of drug action, or validated biomarkers directly associated with HP1BP3. While HP1BP3 is crucial for chromatin structure and cell viability, it is not considered a classic therapeutic target (such as a receptor, enzyme, or transporter). No literature implicates HP1BP3 directly in major human diseases such as cancer or neurodegeneration, though it is indispensable for normal development and physiology[1][2].

Other names

Heterochromatin protein 1 binding protein 3HP1-BP74Protein HP1-BP74HP1BP74