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 [].
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 [].
This family consists of shugoshin-like 2 protein (SGOL2, also known as Sgo2 and TRIPIN) from chordates. 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 [].SGOL2 is required for protecting centromeric cohesin during meiosis but is dispensable for mitosis. Loss of SGOL2 in humans and mice causes infertility in both males and females [, ].
The Shugoshin (SGO) protein family plays a major role in the protection of centromeric cohesion in Drosophila and yeast. This entry represents plant shugoshins, including SGO1 and SGO2 from Arabidopsis [, ]. SGO1 is required for the maintenance of centromeric cohesion of sister chromatids in meiosis I, but not through the control of AtSYN1/AtREC8 localisation. Together with SGO2, it is required for protection of centromeric cohesion during anaphase I []. However, SGO2 is dispensable for meiosis. In rice, OsSGO1 is also involved in the assembly and maintenance of the synaptonemal complex (SC) during early prophase I []. In maize, ZmSGO1 is required for maintenance of centromeric cohesion before prophase II and correct segregation of chromatids during meiosis II [].
