Copper metallochaperone essential for the maturation of cytochrome c oxidase subunit II (MT-CO2/COX2). Together with SCO2, involved in delivering copper to the Cu(A) site on MT-CO2/COX2 (PubMed:15229189, PubMed:15659396, PubMed:16735468, PubMed:17189203, PubMed:19336478). Plays an important role in the regulation of copper homeostasis by controlling the abundance and cell membrane localization of copper transporter CTR1 (By similarity). {ECO:0000250|UniProtKB:Q5SUC9, ECO:0000269|PubMed:15229189, ECO:0000269|PubMed:15659396, ECO:0000269|PubMed:16735468, ECO:0000269|PubMed:17189203, ECO:0000269|PubMed:19336478}. This is the function of Ensembl gene identifier ENSG00000133028 (SCO1, synthesis of cytochrome C oxidase 1).