CAP superfamily
cap superfamily
The CAP superfamily ( cysteine-rich secretory proteins, antigen 5, and pathogenesis-related 1 proteins (CAP)) is a large superfamily of secreted proteins that are produced by a wide range of organisms, including prokaryotes and non- vertebrate eukaryotes.    Members are most often secreted and have an extracellular endocrine or paracrine function and are involved in processes including the regulation of extracellular matrix and branching morphogenesis, potentially as either proteases or protease inhibitors; in ion channel regulation in fertility ; as tumour suppressor or pro- oncogenic genes in tissues including the prostate ; and in cell-cell adhesion during fertilisation.    The overall protein structural conservation within the CAP superfamily results in fundamentally similar functions for the CAP domain in all members, yet the diversity outside of this core region dramatically alters the target specificity and, thus, the biological consequences.