title: RNA- binding protein Stau2 is important for spindle integrity and meiosis progression in mouse oocytes.
abstract: Staufen2 (Stau2) is a double-stranded RNA-binding protein involved in cell fate decision by regulating mRNA transport, mRNA stability, translation, and ribonucleoprotein assembly. Little is known about Stau2 expression and function in mammalian oocytes during meiosis. Herein we report the sub-cellular distribution and function of Stau2 in mouse oocyte meiosis. Western blot analysis revealed high and stable expression of Stau2 in oocytes from germinal vesicle (GV) to metaphase II (MII). Immunofluorescence showed that Stau2 was evenly distributed in oocytes at GV stage, and assembled as filaments after germinal vesicle breakdown (GVBD), particularly, colocalized with spindle at MI and MII. Stau2 was disassembled when microtubules were disrupted with nocodazole, on the other hand, when MTs were stabilized with taxol, Stau2 was not colocalized with the stabilized microtubules, but aggregated around the chromosomes array, indicating Stau2 assembly and colocalization with microtubules require both microtubule integrity and its normal dynamics. During interphase and mitosis of BHK and MEF cells, Stau2 was not distributed on microtubules, but colocalized with cis-Golgi marker GM130, implying its association with Golgi complex but not the spindle in fully differentiated somatic cells. Specific morpholino oligo-mediated Stau2 knockdown disrupted spindle formation, chromosome alignment and microtubule-kinetochore attachment in oocytes. The majority oocytes were arrested at MI stage, with bright MAD1 at kinetochores, indicating activation of spindle assembly checkpoint (SAC). Some oocytes were stranded at telophase I (TI), implying suppressed first polar body extrution. Together these data demonstrate that Stau2 is required for spindle formation and timely meiotic progression in mouse oocytes.
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Cao
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Juan
authors.initials: J
authors.lastname: Du
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Chen
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Nana
authors.initials: N
authors.lastname: Zhang
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Liu
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Liu
authors.affiliation: b Experimental Center for Basic Medical Teaching, School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Jing
authors.initials: J
authors.lastname: Weng
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Yuanjing
authors.initials: Y
authors.lastname: Liang
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ma
mesh_terms: D000818:Animals; D033481:Chromosomes, Mammalian / Q000378:metabolism; D005260:Female; D055785:Gene Knockdown Techniques; D018386:Kinetochores / Q000378:metabolism; D059566:M Phase Cell Cycle Checkpoints; D008540:Meiosis; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008870:Microtubules / Q000378:metabolism; D008938:Mitosis; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009865:Oocytes / Q000166:cytology* / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D008941:Spindle Apparatus / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins; C471845:stau2 protein, mouse
keywords: 1st PBE; Stau2; meiosis; mouse; oocyte; spindle formation