GINS Complex Subunit 1 (GINS1)

The yeast heterotetrameric GINS complex is made up of Sld5 (GINS4), Psf1, Psf2 (GINS2), and Psf3 (GINS3). The formation of the GINS complex is essential for the initiation of DNA replication in yeast and Xenopus egg extracts.

The 3-prime UTR contains a complex array of Alu repeats and partial LINE sequences, and the deduced protein contains 196 amino acids. Northern blot analysis detected moderate expression in thymus, testis, KG-1 cells, and HeLa cells, with low expression in small intestine and colon, and no expression in the other tissues examined.Without GINS, neither Dpb11, which is a homolog of TOPBP1, nor Cdc45 associated properly with chromatin DNA. Without Dpb11 and Sld3, GINS did not associate with replication origins. Genetic and 2-hybrid analysis suggested that GINS interacted with Sld3 and Dpb11.