MULTIPOLAR SPINDLE 1 (MPS1), a novel coiled-coil protein of Arabidopsis thaliana, is required for meiotic spindle organization.
The spindle is essential for chromosome segregation during meiosis, but the molecular mechanism of meiotic spindle organization in higher plants is still not well understood. Here, we report on the identification and characterization of a plant-specific protein, MULTIPOLAR SPINDLE 1 (MPS1), which is involved in spindle organization in meiocytes of Arabidopsis thaliana. The homozygous mps1 mutant exhibits male and female sterility. Light microscopy showed that mps1 mutants produced multiple uneven spores during anther development, most of which aborted in later stages. Cytological analysis showed that chromosome segregation was abnormal in mps1 meiocytes. Immunolocalization showed unequal bipolar or multipolar spindles in mps1 meiocytes, which indicated that aberrant spindles resulted in disordered chromosome segregation. MPS1 encodes a 377-amino-acid protein with putative coiled-coil motifs. In situ hybridization analysis showed that MPS1 is strongly expressed in meiocytes.
Jiang
Hua
H
Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai 200433, China.
Wang
Fen-Fei
FF
Wu
Yu-Ting
YT
Zhou
Xi
X
Huang
Xue-Yong
XY
Zhu
Jun
J
Gao
Ju-Fang
JF
Dong
Rui-Bin
RB
Cao
Kai-Ming
KM
Yang
Zhong-Nan
ZN
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D020090:Chromosome Segregation; D003001:Cloning, Molecular; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D008540:Meiosis; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D010802:Phylogeny; D051479:Plant Infertility; D008941:Spindle Apparatus / Q000378:metabolism*
D029681:Arabidopsis Proteins