Role of ER export signals in controlling surface potassium channel numbers.
Little is known about the identity of endoplasmic reticulum (ER) export signals and how they are used to regulate the number of proteins on the cell surface. Here, we describe two ER export signals that profoundly altered the steady-state distribution of potassium channels and were required for channel localization to the plasma membrane. When transferred to other potassium channels or a G protein-coupled receptor, these ER export signals increased the number of functional proteins on the cell surface. Thus, ER export of membrane proteins is not necessarily limited by folding or assembly, but may be under the control of specific export signals.
Ma
D
D
Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143-0725, USA.
Zerangue
N
N
Lin
Y F
YF
Collins
A
A
Yu
M
M
Jan
Y N
YN
Jan
L Y
LY
D016475:3T3 Cells; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D019556:COS Cells; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; D006031:Glycosylation; D006056:Golgi Apparatus / Q000378:metabolism; D051663:Kv1.2 Potassium Channel; D051379:Mice; D008969:Molecular Sequence Data; D009865:Oocytes; D015221:Potassium Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D024661:Potassium Channels, Inwardly Rectifying; D024642:Potassium Channels, Voltage-Gated; D017510:Protein Folding; D021382:Protein Sorting Signals; D021381:Protein Transport; D018080:Receptors, GABA-B / Q000737:chemistry / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000737:chemistry / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D047488:Retinoid X Receptors; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism; D014981:Xenopus
D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; C496970:Kcna2 protein, mouse; D051663:Kv1.2 Potassium Channel; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D024642:Potassium Channels, Voltage-Gated; D021382:Protein Sorting Signals; D018080:Receptors, GABA-B; D018168:Receptors, Retinoic Acid; D011993:Recombinant Fusion Proteins; D047488:Retinoid X Receptors; D014157:Transcription Factors