Chemotactically directed redistribution of alpha-actinin precedes morphological polarization and reversal of polarity in human polymorphonuclear leucocytes (PMNs).
We have determined the temporal and spatial relationship between cell polarization and alpha-actinin localization by analysing the redistribution of alpha-actinin and F-actin in spherical PMNs developing polarity and in polarized cells reversing polarity following localized stimulation with chemotactic peptide using micropipettes. Initially spherical PMNs develop a one-sided accumulation of alpha-actinin before lamellipodia enriched in alpha-actinin are formed. In polarized cells, alpha-actinin is concentrated at the leading front. When polarity is reversed, alpha-actinin redistribution to the uropod precedes reversal of morphological polarity and formation of new lamellipodia at the uropod. Later, lamellipodia enriched in F-actin and alpha-actinin develop at the former uropod to form a new front. The data document that redistribution of alpha-actinin is a very early event in the development of polarity, which precedes formation of lamellipodia.
Zadeh
Alireza Dehghani
AD
Institute of Pathology, University of Bern, Bern, Switzerland.
Keller
Hansuli
H
D000185:Actinin / Q000378:metabolism*; D000199:Actins / Q000378:metabolism; D016764:Cell Polarity / Q000502:physiology*; D002634:Chemotaxis, Leukocyte / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D009842:Oligopeptides / Q000494:pharmacology
D000199:Actins; D009842:Oligopeptides; D000185:Actinin; C021642:F-chemotactic peptide