HomP1

HomP1 is a protein encoded by the HOMP1 gene located on chromosome 12p13.2 in Homo sapiens. It has a predicted molecular weight of approximately 45 kDa and consists of a single WD40 repeat domain that mediates protein–protein interactions. The protein is predominantly expressed in neuronal tissues, with higher transcript levels in the cerebral cortex, cerebellum and spinal cord. Subcellular localization studies have shown that HomP1 is found in the cytoplasm and perinuclear region, and it co‑localizes with microtubules in cultured neurons.

Functional assays suggest that HomP1 binds to microtubule-associated proteins such as MAP2, and it may play a role in stabilizing microtubule networks during neuronal differentiation. Loss‑of‑function experiments in mouse models result in impaired axonal guidance and motor coordination deficits, indicating a requirement for normal HomP1 activity in nervous system development. In vitro, HomP1 is phosphorylated by casein kinase II, and this post‑translational modification appears to regulate its interaction with other cytoskeletal proteins.

Homologs of HomP1 are found in a range of vertebrate species, including mice, rats, chickens and zebrafish, indicating a conserved evolutionary role. While no direct disease associations have been reported in human genetic studies, alterations in its expression have been observed in transcriptome datasets of Alzheimer’s disease and amyotrophic lateral sclerosis, suggesting a potential involvement in neurodegenerative conditions.

The precise molecular mechanisms by which HomP1 contributes to neuronal architecture and function remain subjects of ongoing research. Further studies, including proteomic interactions and knockout phenotyping, are needed to clarify its roles within the central nervous system.