A human protein containing multiple types of protease-inhibitory modules

Area of Science:

• Genomics
• Molecular Biology
• Proteomics

Background:

• Human chromosome 16p13.3 harbors genes with diverse functions.
• Secreted proteins often play crucial roles in intercellular communication and extracellular matrix regulation.
• Protease inhibitors are vital for maintaining physiological homeostasis and preventing pathological processes.

Purpose of the Study:

• To identify and characterize novel genes and their encoded proteins from human chromosome 16p13.3.
• To elucidate the domain structure and potential function of a newly identified secreted protein.
• To investigate the tissue expression pattern of the novel gene and its encoded protein.

Main Methods:

• Homology-search and gene-finding programs for genomic analysis.
• cDNA sequencing from a lung cDNA library to confirm gene prediction.
• Tissue expression profiling using Northern blotting or similar techniques.

Main Results:

• A novel gene, WFIKKN, was identified on human chromosome 16p13.3.
• The WFIKKN gene encodes a secreted protein with multiple functional domains: whey acidic protein (WAP), follistatin (FS) module, immunoglobulin (Ig) domain, Kunitz-type protease inhibitor (KU) domains, and NTR-module.
• The WFIKKN gene is intron-depleted and expressed in pancreas, kidney, liver, placenta, and lung.
• The protein's domain composition suggests a role as a multivalent protease inhibitor.

Conclusions:

• The WFIKKN gene encodes a unique secreted protein with a complex domain structure.
• The WFIKKN protein is a potential multivalent inhibitor of serine proteases and metalloproteinases.
• This finding opens new avenues for understanding protease regulation in various physiological and pathological contexts.