背景资料：Capillary morphogenesis protein 1 (CMG1), also known as intraflagellar transport protein 74 (ITP74) or coiled-coil domain-containing protein 2 (CCDC2), is a 600 amino acid human homologue of IFT-71, a complex B protein supporting intraflagellar transport (IFT) in Chlamydomonas. CMG1 localizes to the cytoplasmic vesicle and is highly expressed in adult and fetal kidney and testis, with lower levels of expression in adult heart, placenta, lung, liver and pancreas, and in fetal heart, lung and liver. CMG1 has been suggested to have a role in the primary cilia of HUVEC, and it also functions as a transcriptional regulator of cyclin D2 in spermatocyte-derived cells.