Dynamics of membrane exchange of the plasma membrane and the lysis of isolated protoplasts during rapid expansions in area

Summary The plasma membrane of protoplasts isolated from rye leaves (Secale cereale L. cv. Puma) can withstand a maximum elastic stretching of about 2%. Larger area expansions involve the incorporation of new material into the membrane. The dynamics of this process during expansion from isotonic solutions and the probable frequency of lysis have been measured as a function of membrane tension in populations of protoplasts isolated from both cold-acclimated and nonacclimated plants. To a first approximation, both increase exponentially with tension. An analytical solution is reported for the membrane tension as a function of time during an arbitrary expansion in area.