PPIAL4A Gene: Function, Expression, and Disease Relevance

PPIAL4A is a protein-coding gene located on chromosome 1q21.1. It belongs to the cyclophilin family of peptidylprolyl isomerases, which catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and accelerate protein folding. The encoded protein is highly similar to cyclophilin A (PPIA) and may function in protein folding, intracellular trafficking, and immune modulation. PPIAL4A is part of a gene cluster that has undergone segmental duplications, and its expression is detected in various tissues and cancer cell lines.

Disease category	Pathophysiological mechanism	Genomic evidence
Cancer (general)	Overexpression may contribute to tumorigenesis via altered protein folding and signaling	COSMIC database reports somatic mutations in multiple cancer types
Breast cancer	Potential role in proliferation and metastasis	COSMIC mutation data
Lung cancer	Somatic variants observed	COSMIC mutation data

The PPIAL4A protein is a cyclophilin-type peptidylprolyl isomerase that catalyzes the cis-trans isomerization of proline residues, facilitating protein folding and conformational changes. It shares high sequence similarity with cyclophilin A and may participate in cellular processes such as protein trafficking, signal transduction, and immune response. The protein is localized in the cytoplasm and nucleus, and its expression is regulated in a tissue-specific manner.