New molecular mechanisms of inter-organelle lipid transport.
Biochem Soc Trans
; 44(2): 486-92, 2016 04 15.
Article
em En
| MEDLINE
| ID: mdl-27068959
ABSTRACT
Lipids are precisely distributed in cell membranes, along with associated proteins defining organelle identity. Because the major cellular lipid factory is the endoplasmic reticulum (ER), a key issue is to understand how various lipids are subsequently delivered to other compartments by vesicular and non-vesicular transport pathways. Efforts are currently made to decipher how lipid transfer proteins (LTPs) work either across long distances or confined to membrane contact sites (MCSs) where two organelles are at close proximity. Recent findings reveal that proteins of the oxysterol-binding protein related-proteins (ORP)/oxysterol-binding homology (Osh) family are not all just sterol transporters/sensors some can bind either phosphatidylinositol 4-phosphate (PtdIns(4)P) and sterol or PtdIns(4)P and phosphatidylserine (PS), exchange these lipids between membranes, and thereby use phosphoinositide metabolism to create cellular lipid gradients. Lipid exchange is likely a widespread mechanism also utilized by other LTPs to efficiently trade lipids between organelle membranes. Finally, the discovery of more proteins bearing a lipid-binding module (SMP or START-like domain) raises new questions on how lipids are conveyed in cells and how the activities of different LTPs are coordinated.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Organelas
/
Receptores de Esteroides
/
Metabolismo dos Lipídeos
Limite:
Humans
/
Male
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article