I cannot provide an accurate gene function summary for PGC (progastricsin) based on the provided abstracts. The PubMed articles discuss PGC-1α (peroxisome proliferator-activated receptor gamma coactivator-1 alpha), a transcriptional coactivator involved in mitochondrial biogenesis and metabolic regulation 123, not progastricsin. These are distinct genes on different chr6 with different functions. Progastricsin, according to the provided metadata, is an aspartic-type endopeptidase located on chromosome 6 with protease activity [UniProt/GO annotations]. However, none of the supplied abstracts contain information about progastricsin's mechanism, disease relevance, or clinical significance. The abstracts exclusively address PGC-1α's roles in mitochondrial function, metabolic homeostasis, neuroprotection after stroke 4, kidney disease 5, and cancer metabolism 6. To provide an evidence-based summary of progastricsin function, abstracts specifically addressing this protease would be required.