Abstract:
:We have studied tubules formed from a polymerizable lipid in aqueous dispersion using freeze-fracture replication and transmission electron microscopy. The polymerizable diacetylenic lecithin 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine converts from liposomes to hollow cylinders, which we call tubules, on cooling through its chain melting phase transition temperature. These tubules differ substantially from cochleate cylinders formed by phosphatidylserines on binding of calcium. The tubules have diameters that range from 0.3 to 1 mum and lengths of up to hundreds of micrometers depending on conditions of formation. The thickness of the walls varies from as few as two bilayers to tens of bilayers in some longer tubules. Their surfaces may be either smooth, gently rippled, or with spiral steps depending on sample preparation conditions, including whether the lipids have been polymerized. The spiral steps may reflect the growth of the tubules by rolling up of flattened liposomes.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Yager P,Schoen PE,Davies C,Price R,Singh Adoi
10.1016/S0006-3495(85)83852-2subject
Has Abstractpub_date
1985-12-01 00:00:00pages
899-906issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(85)83852-2journal_volume
48pub_type
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