This family consists of shugoshin 1 (Sgo1, also known as SGOL1) from chordates. SGOL1 may act by preventing phosphorylation of the stag2 subunit of cohesin complex at the centromere, ensuring cohesin persistence at centromere until cohesin cleavage by espl1/separase at anaphase [].Shugoshin (which is Japanese for guardian spirit) was first identified in Drosophila melanogaster (originally named Mei-S322) as a protein that is required for sister chromatid cohesion []. Later, a few shugoshin orthologs from yeast to human were identified through similarities in their sequence architectures []. Flies and budding yeast have only one known shugoshin (Mei-S322 and Sgo1, respectively), fission yeast, Xenopus laevis and mammals have two shugoshin-like proteins (Sgo1 and Sgo2 in yeast and SGOL1 and SGOL2 in vertebrates) [].The functions of Sgo1 from different species can vary. For instance, in S. cevervisiae and D. melanogaster, Sgo1 protects cohesion at meiosis but not mitosis. In humans and X. laevis, SGOL1 protect centromeric cohesion during mitosis [].
