Chromosome segregation in mitosis is orchestrated by the interaction of the kinetochore with spindle microtubules. Our recent study shows that NEK2A interacts with MAD 1 at the kinetochore and possibly functions as a ...Chromosome segregation in mitosis is orchestrated by the interaction of the kinetochore with spindle microtubules. Our recent study shows that NEK2A interacts with MAD 1 at the kinetochore and possibly functions as a novel integrator of spindle checkpoint signaling. However, it is unclear how NEK2A regulates kinetochore-microtubule attachment in mitosis. Here we show that NEK2A phosphorylates human Sgo 1 and such phosphorylation is essential for faithful chromosome congression in mitosis. NEK2A binds directly to HsSgol in vitro and co-distributes with HsSgol to the kinetochore of mitotic cells. Our in vitro phosphorylation experiment demonstrated that HsSgo 1 is a substrate of NEK2A and the phosphorylation sites were mapped to Ser^14 and Ser^507 as judged by the incorporation of 32^P. Although such phosphorylation is not required for assembly of HsSgo 1 to the kinetochore, expression of non-phosphorylatable mutant HsSgo 1 perturbed chromosome congression and resulted in a dramatic increase in microtubule attachment errors, including syntelic and monotelic attachments. These findings reveal a key role for the NEK2A-mediated phosphorylation ofHsSgo 1 in orchestrating dynamic kinetochore-microtubule interaction. We propose that NEK2A-mediated phosphorylation of human Sgo 1 provides a link between centromeric cohesion and spindle microtubule attachment at the kinetochores.展开更多
Shugoshin-1(Sgo1)is necessary for maintaining sister centromere cohesion and ensuring accurate chromosome segregation during mitosis.It has been reported that the localization of Sgo1 at the centromere is dependent on...Shugoshin-1(Sgo1)is necessary for maintaining sister centromere cohesion and ensuring accurate chromosome segregation during mitosis.It has been reported that the localization of Sgo1 at the centromere is dependent on Bub1-mediated phosphorylation of histone H2A at T120.However,it remains uncertain whether other centromeric proteins play a role in regulating the localization and function of Sgo1 during mitosis.Here,we show that CENP-A interacts with Sgo1 and determines the localization of Sgo1 to the centromere during mitosis.Further biochemical characterization revealed that lysine and arginine residues in the C-terminal domain of Sgo1 are critical for binding CENP-A.Interestingly,the replacement of these basic amino acids with acidic amino acids perturbed the localization of Sgo1 and Aurora B to the centromere,resulting in aberrant chromosome segregation and premature chromatid separation.Taken together,these findings reveal a previously unrecognized but direct link between Sgo1 and CENP-A in centromere plasticity control and illustrate how the Sgo1–CENP-A interaction guides accurate cell division.展开更多
基金We thank members of our group for insightful discussion during the course of this study.This work was supported by grants from Chinese Academy of Science(KSCX1-YW-R65,KSCX2-YW-H10)National Basic Research Program of China(2002CB713700)+4 种基金Hi-Tech Research and Development Program of China(2001AA215331)Chinese Minister of Education(20020358051 to XY,PCSIRT0413 to XD)National Natural Science Foundation of China(39925018,30270293 to XY,30500183 to XD,30600222 to JY)National Institutes of Health(USA)(DK56292,CA92080)to XY(a Georgia Cancer Coalition Eminent Scholar)JY was supported by China Postdoctor(2005037560).
文摘Chromosome segregation in mitosis is orchestrated by the interaction of the kinetochore with spindle microtubules. Our recent study shows that NEK2A interacts with MAD 1 at the kinetochore and possibly functions as a novel integrator of spindle checkpoint signaling. However, it is unclear how NEK2A regulates kinetochore-microtubule attachment in mitosis. Here we show that NEK2A phosphorylates human Sgo 1 and such phosphorylation is essential for faithful chromosome congression in mitosis. NEK2A binds directly to HsSgol in vitro and co-distributes with HsSgol to the kinetochore of mitotic cells. Our in vitro phosphorylation experiment demonstrated that HsSgo 1 is a substrate of NEK2A and the phosphorylation sites were mapped to Ser^14 and Ser^507 as judged by the incorporation of 32^P. Although such phosphorylation is not required for assembly of HsSgo 1 to the kinetochore, expression of non-phosphorylatable mutant HsSgo 1 perturbed chromosome congression and resulted in a dramatic increase in microtubule attachment errors, including syntelic and monotelic attachments. These findings reveal a key role for the NEK2A-mediated phosphorylation ofHsSgo 1 in orchestrating dynamic kinetochore-microtubule interaction. We propose that NEK2A-mediated phosphorylation of human Sgo 1 provides a link between centromeric cohesion and spindle microtubule attachment at the kinetochores.
基金supported by grants from the Ministry of Science and Technology of China(2022YFA1303100,2022YFA0806800,2022YFA1302700,and 2017YFA0503600)the National Natural Science Foundation of China(32090040,92254302,92153302,32170733,31621002,and 22177106)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB19040000 and XDB37010105)the Ministry of Education(IRT_17R102,20113402130010,and YD2070006001).
文摘Shugoshin-1(Sgo1)is necessary for maintaining sister centromere cohesion and ensuring accurate chromosome segregation during mitosis.It has been reported that the localization of Sgo1 at the centromere is dependent on Bub1-mediated phosphorylation of histone H2A at T120.However,it remains uncertain whether other centromeric proteins play a role in regulating the localization and function of Sgo1 during mitosis.Here,we show that CENP-A interacts with Sgo1 and determines the localization of Sgo1 to the centromere during mitosis.Further biochemical characterization revealed that lysine and arginine residues in the C-terminal domain of Sgo1 are critical for binding CENP-A.Interestingly,the replacement of these basic amino acids with acidic amino acids perturbed the localization of Sgo1 and Aurora B to the centromere,resulting in aberrant chromosome segregation and premature chromatid separation.Taken together,these findings reveal a previously unrecognized but direct link between Sgo1 and CENP-A in centromere plasticity control and illustrate how the Sgo1–CENP-A interaction guides accurate cell division.
