EFHC1, a protein mutated in juvenile myoclonic epilepsy, associates with the mitotic spindle through its N-terminus.
A novel gene, EFHC1, mutated in juvenile myoclonic epilepsy (JME) encodes a protein with three DM10 domains of unknown function and one putative EF-hand motif. To study the properties of EFHC1, we expressed EGFP-tagged protein in various cell lines. In interphase cells, the fusion protein was present in the cytoplasm and in the nucleus with specific accumulation at the centrosome. During mitosis EGFP-EFHC1 colocalized with the mitotic spindle, especially at spindle poles and with the midbody during cytokinesis. Using a specific antibody, we demonstrated the same distribution of the endogenous protein. Deletion analyses revealed that the N-terminal region of EFHC1 is crucial for the association with the mitotic spindle and the midbody. Our results suggest that EFHC1 could play an important role during cell division.
de Nijs
Laurence
L
Center for Cellular and Molecular Neurobiology, University of Liège, Avenue de l'Hôpital 1, B-36, 4000 Liège, Belgium.
Lakaye
Bernard
B
Coumans
Bernard
B
Léon
Christine
C
Ikeda
Takashi
T
Delgado-Escueta
Antonio V
AV
Grisar
Thierry
T
Chanas
Grazyna
G
D000818:Animals; D019556:COS Cells; D002135:Calcium-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002455:Cell Division; D002467:Cell Nucleus / Q000378:metabolism; D018385:Centrosome / Q000378:metabolism; D002522:Chlorocebus aethiops; D003593:Cytoplasm / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D009154:Mutation; D020190:Myoclonic Epilepsy, Juvenile / Q000235:genetics; D041681:NIH 3T3 Cells; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D008941:Spindle Apparatus / Q000378:metabolism*; D014162:Transfection; D014407:Tumor Cells, Cultured
D002135:Calcium-Binding Proteins; C489648:EFHC1 protein, human; D011993:Recombinant Fusion Proteins