Myelin basic protein co-distributes with other PI(4,5)P2-sequestering proteins in Triton X-100 detergent-resistant membrane microdomains.
The 18.5kDa isoform of myelin basic protein (MBP) has recently been shown to sequester phosphatidylinositol-(4,5)-bis-phosphate (PI(4,5)P(2)) in vesicular membranes in vitro, as do domains of other membrane- and cytoskeleton-associated proteins such as MARCKS (myristoylated alanine-rich C kinase substrate) and GAP-43 (growth-associated protein of 43kDa), known collectively as "PI(4,5)P(2)-modulins" [Musse et al., Biochemistry, 47 (2008) 10372-10382 (doi:10.1021/bi801302b)]. Here, we demonstrate co-localisation of MBP and MARCKS in primary rat oligodendrocytes, and co-distribution of MBP, MARCKS, and GAP-43 in lipid raft fractions recovered from Triton X-100 detergent-extracted isolated myelin and brain homogenates. The results lend further support to MBP's multifunctionality, particularly as an additional modulator of PI(4,5)P(2) availability in myelin.
Musse
Abdiwahab A
AA
Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, Ontario, Canada.
Gao
Wen
W
Rangaraj
Godha
G
Boggs
Joan M
JM
Harauz
George
G
D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism; D002478:Cells, Cultured; D003902:Detergents / Q000494:pharmacology; D019922:GAP-43 Protein / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D018613:Microscopy, Confocal; D004676:Myelin Basic Protein; D000076250:Myristoylated Alanine-Rich C Kinase Substrate; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D017830:Octoxynol / Q000494:pharmacology; D009836:Oligodendroglia / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D014157:Transcription Factors / Q000378:metabolism*
D003902:Detergents; D019922:GAP-43 Protein; D047908:Intracellular Signaling Peptides and Proteins; C000619712:Marcks protein, rat; C436006:Mbp protein, rat; D008565:Membrane Proteins; D004676:Myelin Basic Protein; D009419:Nerve Tissue Proteins; D014157:Transcription Factors; D000076250:Myristoylated Alanine-Rich C Kinase Substrate; D017830:Octoxynol