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- **********************
- * Oleosins signature *
- **********************
-
- Oleosins [1] are the proteinaceous components of plants' lipid storage bodies
- called oil bodies. Oil bodies are small droplets (0.2 to 1.5 mu-m in diameter)
- containing mostly triacylglycerol that are surrounded by a phospholipid/
- oleosin annulus. Oleosins may have a structural role in stabilizing the lipid
- body during dessication of the seed, by preventing coalescence of the oil.
- They may also provide recognition signals for specific lipase anchorage in
- lipolysis during seedling growth. Oleosins are found in the monolayer lipid/
- water interface of oil bodies and probably interact with both the lipid and
- phospholipid moieties.
-
- Oleosins are proteins of 16 Kd to 24 Kd and are composed of three domains: an
- N-terminal hydrophilic region of variable length (from 30 to 60 residues); a
- central hydrophobic domain of about 70 residues and a C-terminal amphipathic
- region of variable length (from 60 to 100 residues). The central hydrophobic
- domain is proposed to be made up of beta-strand structure and to interact with
- the lipids [2]. It is the only domain whose sequence is conserved and we
- have therefore selected a section from that domain as a signature pattern.
-
- -Consensus pattern: [AG]-[ST]-x(2)-[AG]-x(2)-[LIVM]-[SA]-T-P-[LIVMF](4)-F-S-P-
- [LIVM](3)-P-A
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
- -Last update: October 1993 / First entry.
-
- [ 1] Murphy D.J., Keen J.N., O'Sullivan J.N., Au D.M.Y., Edwards E.-W.,
- Jackson P.J., Cummins I., Gibbons T., Shaw C.H., Ryan A.J.
- Biochim. Biophys. Acta 1088:86-94(1991).
- [ 2] Tzen J.T.C., Lie G.C., Huang A.H.C.
- J. Biol. Chem. 267:15626-15634(1992).
-