Abstract:
:Mechanisms that enabled primitive cell membranes to self-reproduce have been discussed based on the physicochemical properties of fatty acids; however, there must be a transition to modern cell membranes composed of phospholipids [Budin I, Szostak JW (2011) Proc Natl Acad Sci USA 108:5249-5254]. Thus, a growth-division mechanism of membranes that does not depend on the chemical nature of amphiphilic molecules must have existed. Here, we show that giant unilamellar vesicles composed of phospholipids can undergo the coupled process of fusion and budding transformation, which mimics cell growth and division. After gaining excess membrane by electrofusion, giant vesicles spontaneously transform into the budded shape only when they contain macromolecules (polymers) inside their aqueous core. This process is a result of the vesicle maximizing the translational entropy of the encapsulated polymers (depletion volume effect). Because the cell is a lipid membrane bag containing highly concentrated biopolymers, this coupling process that is induced by physical and nonspecific interactions may have a general importance in the self-reproduction of the early cellular compartments.
journal_name
Proc Natl Acad Sci U S Aauthors
Terasawa H,Nishimura K,Suzuki H,Matsuura T,Yomo Tdoi
10.1073/pnas.1120327109subject
Has Abstractpub_date
2012-04-17 00:00:00pages
5942-7issue
16eissn
0027-8424issn
1091-6490pii
1120327109journal_volume
109pub_type
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