TY - JOUR
T1 - Organization of microtubules in centrosome-free cytoplasm
AU - McNiven, M. A.
AU - Porter, K. R.
PY - 1988
Y1 - 1988
N2 - Many different cell types possess microtubule patterns which appear to be polarized and oriented, in part, by cytoplasmic factors not directly associated with a centrosome. Recently, we demonstrated that cytoplasmic extensions ('arms') of teleost melanophores will reorganize their microtubule population outward from their centers after surgical isolation (McNiven, M.A., M. Wang, and K.R. Porter. 1984. Cell. 37:753-765). In the study reported here, we examine microtubule dynamics within the centrosome-free fragments and find that, after severing, microtubule reorganization is initiated at the proximal (cut) end of an arm and migrates distally with the aggregated pigment mass until it becomes permanently positioned at the middle of the arm. Computer-aided image analysis demonstrates that this middle position is located at the arm centroid, implicating the action of a cytoplasmic gel in this process. Morphological studies of arms devoid of pigment reveal that microtubules do not emanate from a single site or structure within the centroid area, but from a more generalized region. Taken together, these findings suggest that factors distributed throughout cytoplasm participate in microtubule assembly and organization.
AB - Many different cell types possess microtubule patterns which appear to be polarized and oriented, in part, by cytoplasmic factors not directly associated with a centrosome. Recently, we demonstrated that cytoplasmic extensions ('arms') of teleost melanophores will reorganize their microtubule population outward from their centers after surgical isolation (McNiven, M.A., M. Wang, and K.R. Porter. 1984. Cell. 37:753-765). In the study reported here, we examine microtubule dynamics within the centrosome-free fragments and find that, after severing, microtubule reorganization is initiated at the proximal (cut) end of an arm and migrates distally with the aggregated pigment mass until it becomes permanently positioned at the middle of the arm. Computer-aided image analysis demonstrates that this middle position is located at the arm centroid, implicating the action of a cytoplasmic gel in this process. Morphological studies of arms devoid of pigment reveal that microtubules do not emanate from a single site or structure within the centroid area, but from a more generalized region. Taken together, these findings suggest that factors distributed throughout cytoplasm participate in microtubule assembly and organization.
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U2 - 10.1083/jcb.106.5.1593
DO - 10.1083/jcb.106.5.1593
M3 - Article
C2 - 3286659
AN - SCOPUS:0023916549
SN - 0021-9525
VL - 106
SP - 1593
EP - 1605
JO - Journal of Cell Biology
JF - Journal of Cell Biology
IS - 5
ER -