a-kleisins are core components of meiotic and mitotic cohesin complexes. Arabidopsis contains genes encoding four a-kleisins. SYN1, a REC8 ortholog, is essential for meiosis, while SYN2 and SYN4 appear to be SCCI orth...a-kleisins are core components of meiotic and mitotic cohesin complexes. Arabidopsis contains genes encoding four a-kleisins. SYN1, a REC8 ortholog, is essential for meiosis, while SYN2 and SYN4 appear to be SCCI orthologs and function in mitosis. SYN3 is enriched in the nucleolus of meiotic and mitotic cells and is essential for megagametogenesis. It was recently shown that expression of SYN3-RNAi constructs in buds cause changes in meiotic gene expression that result in meiotic alterations. In this report we show that expression of SYN3 from the 35S promoter with either a c-terminal Myc or FAST tag causes a reduction in SYN1 mRNA levels that results in al- terations in sister chromatid cohesion, homologous chromosome synapsis female meiosis. and synaptonemal complex formation during both male and展开更多
Among multiple genes aberrantly activated in cancers,invariably,there is a group related to the capacity of cell to self-renewal.Some of these genes are related to the normal process of development,including the estab...Among multiple genes aberrantly activated in cancers,invariably,there is a group related to the capacity of cell to self-renewal.Some of these genes are related to the normal process of development,including the establishment of a germline.This group,a part of growing family of Cancer/Testis(CT)genes,now includes the meiosis specific subunits of cohesin complex.The first reports characterizing the SMC1 and RAD21 genes,encoding subunits of cohesin,were published 20 years ago;however the exact molecular mechanics of cohesin molecular machine in vivo remains rather obscure notwithstanding ample elegant experiments.The matters are complicated by the fact that the evolution of cohesin function,which is served by just two basic types of protein complexes in budding yeast,took an explosive turn in Metazoa.The recent characterization of a new set of genes encoding cohesin subunits specific for meiosis in vertebrates adds several levels of complexity to the task of structurefunction analysis of specific cohesin pathways,even more so in relation to their aberrant functionality in cancers.These three proteins,SMC1β,RAD21L and STAG3 are likely involved in a specific function in the first meiotic prophase,genetic recombination,and segregation of homologues.However,at present,it is rather challenging to pinpoint the molecular role of these proteins,particularly in synaptonemal complex or centromere function,due to the multiplicity of different cohesins in meiosis.The roles of these proteins in cancer cell physiology,upon their aberrant activation in tumors,also remain to be elucidated.Nevertheless,as the existence of Cancer/Testis cohesin complexes in tumor cells appears to be all but certain,this brings a promise of a new target for cancer therapy and/or diagnostics.展开更多
基金supported by a grant from the National Science Foundation of USA(No.MCB0718191)
文摘a-kleisins are core components of meiotic and mitotic cohesin complexes. Arabidopsis contains genes encoding four a-kleisins. SYN1, a REC8 ortholog, is essential for meiosis, while SYN2 and SYN4 appear to be SCCI orthologs and function in mitosis. SYN3 is enriched in the nucleolus of meiotic and mitotic cells and is essential for megagametogenesis. It was recently shown that expression of SYN3-RNAi constructs in buds cause changes in meiotic gene expression that result in meiotic alterations. In this report we show that expression of SYN3 from the 35S promoter with either a c-terminal Myc or FAST tag causes a reduction in SYN1 mRNA levels that results in al- terations in sister chromatid cohesion, homologous chromosome synapsis female meiosis. and synaptonemal complex formation during both male and
文摘Among multiple genes aberrantly activated in cancers,invariably,there is a group related to the capacity of cell to self-renewal.Some of these genes are related to the normal process of development,including the establishment of a germline.This group,a part of growing family of Cancer/Testis(CT)genes,now includes the meiosis specific subunits of cohesin complex.The first reports characterizing the SMC1 and RAD21 genes,encoding subunits of cohesin,were published 20 years ago;however the exact molecular mechanics of cohesin molecular machine in vivo remains rather obscure notwithstanding ample elegant experiments.The matters are complicated by the fact that the evolution of cohesin function,which is served by just two basic types of protein complexes in budding yeast,took an explosive turn in Metazoa.The recent characterization of a new set of genes encoding cohesin subunits specific for meiosis in vertebrates adds several levels of complexity to the task of structurefunction analysis of specific cohesin pathways,even more so in relation to their aberrant functionality in cancers.These three proteins,SMC1β,RAD21L and STAG3 are likely involved in a specific function in the first meiotic prophase,genetic recombination,and segregation of homologues.However,at present,it is rather challenging to pinpoint the molecular role of these proteins,particularly in synaptonemal complex or centromere function,due to the multiplicity of different cohesins in meiosis.The roles of these proteins in cancer cell physiology,upon their aberrant activation in tumors,also remain to be elucidated.Nevertheless,as the existence of Cancer/Testis cohesin complexes in tumor cells appears to be all but certain,this brings a promise of a new target for cancer therapy and/or diagnostics.
