Amphiphysin 2 (Bin1) and T-tubule biogenesis in muscle.
In striated muscle, the plasma membrane forms tubular invaginations (transverse tubules or T-tubules) that function in depolarization-contraction coupling. Caveolin-3 and amphiphysin were implicated in their biogenesis. Amphiphysin isoforms have a putative role in membrane deformation at endocytic sites. An isoform of amphiphysin 2 concentrated at T-tubules induced tubular plasma membrane invaginations when expressed in nonmuscle cells. This property required exon 10, a phosphoinositide-binding module. In developing myotubes, amphiphysin 2 and caveolin-3 segregated in tubular and vesicular portions of the T-tubule system, respectively. These findings support a role of the bilayer-deforming properties of amphiphysin at T-tubules and, more generally, a physiological role of amphiphysin in membrane deformation.
Department of Cell Biology and Howard Hughes Medical Institute, Yale University School of Medicine, 295 Congress Avenue, New Haven, CT 06510, USA.
Eunkyung
E
Lee
Melissa
M
Marcucci
Laurie
L
Daniell
Marc
M
Pypaert
Ora A
OA
Weisz
Gian-Carlo
GC
Ochoa
Khashayar
K
Farsad
Markus R
MR
Wenk
Pietro
P
De Camilli
D000818:Animals; D016466:CHO Cells; D051244:Caveolin 3; D022461:Caveolins / Q000378:metabolism; D002454:Cell Differentiation; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D021961:Cell Membrane Structures / Q000378:metabolism / Q000648:ultrastructure*; D006224:Cricetinae; D034281:Dynamins; D005091:Exons; D020558:GTP Phosphohydrolases / Q000378:metabolism; D008081:Liposomes / Q000378:metabolism; D051379:Mice; D008854:Microscopy, Electron; D009024:Morphogenesis; D024510:Muscle Development; D018482:Muscle, Skeletal / Q000378:metabolism / Q000648:ultrastructure*; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000378:metabolism; D020033:Protein Isoforms; D017434:Protein Structure, Tertiary; D034741:RNA, Small Interfering; D022661:RNA, Untranslated / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014162:Transfection
C495548:Cav3 protein, mouse; D051244:Caveolin 3; D022461:Caveolins; D008081:Liposomes; D009419:Nerve Tissue Proteins; D019269:Phosphatidylinositol 4,5-Diphosphate; D020033:Protein Isoforms; D034741:RNA, Small Interfering; D022661:RNA, Untranslated; D011993:Recombinant Fusion Proteins; C075637:amphiphysin; D020558:GTP Phosphohydrolases; D034281:Dynamins