抄録
Gelation of extracts of a myeloid leukemia cell line (M1) was compared before and after differentiation induced with conditioned medium (CM) from rat embryo cells. Although an extract of Mml cells, a macrophage line derived from Ml line, gelled when warmed in the presence of 2 mM MgCl2, undifferentiated M1 cells gelled only after dialysis and a supplement of exogenous actin. After differentiation had been induced, an addition of exogenous actin, but not dialysis, was needed for gelation.
Small amounts of KCl always inhibited the gelation of the control M1 cell extracts, but they promoted gelation of the CM-treated M1 and Mml cell extracts. Thus, the dialysis required for gelation of the control M1 cell extract appears to be necessary for the exclusion of endogenous KCl. Several possible mechanisms for the KCl control of gelation, as well as different requirements of exogenous actin needed for gelation are discussed based on the results of our experiments.
