HHIP protein interactions in lung cells provide insight into COPD pathogenesis

Area of Science:

• Genomics and Bioinformatics
• Molecular Biology
• Pulmonary Medicine

Background:

• Chronic Obstructive Pulmonary Disease (COPD) is a major global health issue with both environmental and genetic risk factors.
• Genome-Wide Association Studies (GWASes) have identified over 80 genetic loci associated with COPD, but the biological networks of these genes remain unclear.
• Understanding gene interactions is crucial for elucidating complex disease pathogenesis.

Purpose of the Study:

• To identify protein-protein interactions of HHIP, a known COPD GWAS gene, in lung cells.
• To explore the network proximity of HHIP to other COPD GWAS genes.
• To gain insights into the functional role of HHIP in COPD pathogenesis.

Main Methods:

• Affinity purification mass spectrometry (AP-MS) was used to identify HHIP interactors in IMR90 and 16HBE lung cell lines.
• A protein-protein interaction network, HUBRIS, was constructed using 8 public databases.
• Newly identified interactions were validated to assess their biological significance.

Main Results:

• Common and cell type-specific protein interactors of HHIP were identified.
• New interactions shortened the network distance between HHIP and other COPD GWAS genes (e.g., DSP, MFAP2, TET2, FBLN5).
• Validated interactions with CAVIN1 and TP53 suggest HHIP's role in oxidative stress response and extracellular matrix organization.

Conclusions:

• HHIP interacts with proteins involved in extracellular matrix and tissue organization, providing new insights into COPD.
• The identified interactions of HHIP with CAVIN1 and TP53 implicate it in the cellular response to oxidative stress.
• This study enhances our understanding of the molecular networks underlying COPD susceptibility genes.