TY - JOUR
T1 - A monoclonal antibody to a mitotic microtubule-associated protein blocks mitotic progression
AU - Nislow, C.
AU - Sellitto, C.
AU - Kuriyama, Ryoko
AU - McIntosh, J. R.
PY - 1990/8
Y1 - 1990/8
N2 - A monoclonal antibody raised against mitotic spindles isolated from CHO cells ([CHO1], Sellitto, C, and R. Kuriyama. 1988. J. Cell Biol. 106:431-439) identifies an epitope that resides on polypeptides of 95 and 105 kD and is localized in the spindles of diverse organisms. The antigen is distributed throughout the spindle at metaphase but becomes concentrated in a progressively narrower zone on either side of the spindle midplane as anaphase progresses. Microinjection of CHO1, either as an ascites fluid or as purified IgM, results in mitotic inhibition in a stage-specific and dose-dependent manner. Parallel control injections with nonimmune IgMs do not yield significant mitotic inhibition. Immunofluorescence analysis of injected cells reveals that those which complete mitosis display normal localization of CHO1, whereas arrested cells show no specific localization of the CHO1 antigen within the spindle. Immunoelectron microscopic images of such arrested cells indicate aberrant microtubule organization. The CHO1 antigen in HeLa cell extracts copurifies with taxolstabilized microtubules. Neither of the polypeptides bearing the antigen is extracted from microtubules by ATP or GTP, but both are ∼60% extracted with 0.5 M NaCl. Sucrose gradient analysis reveals that the antigens sediment at ∼11S. The CHO 1 antigen appears to be a novel mitotic MAP whose proper distribution within the spindle is required for mitosis. The properties of the antigen(s) suggest that the corresponding protein(s) are part of the mechanism that holds the antiparallel microtubules of the two interdigitating half spindles together during anaphase.
AB - A monoclonal antibody raised against mitotic spindles isolated from CHO cells ([CHO1], Sellitto, C, and R. Kuriyama. 1988. J. Cell Biol. 106:431-439) identifies an epitope that resides on polypeptides of 95 and 105 kD and is localized in the spindles of diverse organisms. The antigen is distributed throughout the spindle at metaphase but becomes concentrated in a progressively narrower zone on either side of the spindle midplane as anaphase progresses. Microinjection of CHO1, either as an ascites fluid or as purified IgM, results in mitotic inhibition in a stage-specific and dose-dependent manner. Parallel control injections with nonimmune IgMs do not yield significant mitotic inhibition. Immunofluorescence analysis of injected cells reveals that those which complete mitosis display normal localization of CHO1, whereas arrested cells show no specific localization of the CHO1 antigen within the spindle. Immunoelectron microscopic images of such arrested cells indicate aberrant microtubule organization. The CHO1 antigen in HeLa cell extracts copurifies with taxolstabilized microtubules. Neither of the polypeptides bearing the antigen is extracted from microtubules by ATP or GTP, but both are ∼60% extracted with 0.5 M NaCl. Sucrose gradient analysis reveals that the antigens sediment at ∼11S. The CHO 1 antigen appears to be a novel mitotic MAP whose proper distribution within the spindle is required for mitosis. The properties of the antigen(s) suggest that the corresponding protein(s) are part of the mechanism that holds the antiparallel microtubules of the two interdigitating half spindles together during anaphase.
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U2 - 10.1083/jcb.111.2.511
DO - 10.1083/jcb.111.2.511
M3 - Article
C2 - 2199459
AN - SCOPUS:0025351621
SN - 0021-9525
VL - 111
SP - 511
EP - 522
JO - Journal of Cell Biology
JF - Journal of Cell Biology
IS - 2
ER -