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- W2065524119 abstract "The mucolipin TRP (TRPML) proteins are a family of endolysosomal cation channels with genetically established importance in humans and rodent. Mutations of human TRPML1 cause type IV mucolipidosis, a devastating pediatric neurodegenerative disease. Our recent electrophysiological studies revealed that, although a TRPML1-mediated current can only be recorded in late endosome and lysosome (LEL) using the lysosome patch clamp technique, a proline substitution in TRPML1 (TRPML1V432P) results in a large whole cell current. Thus, it remains unknown whether the large TRPML1V432P-mediated current results from an increased surface expression (trafficking), elevated channel activity (gating), or both. Here we performed systemic Pro substitutions in a region previously implicated in the gating of various 6 transmembrane cation channels. We found that several Pro substitutions displayed gain-of-function (GOF) constitutive activities at both the plasma membrane (PM) and endolysosomal membranes. Although wild-type TRPML1 and non-GOF Pro substitutions localized exclusively in LEL and were barely detectable in the PM, the GOF mutations with high constitutive activities were not restricted to LEL compartments, and most significantly, exhibited significant surface expression. Because lysosomal exocytosis is Ca2+-dependent, constitutive Ca2+ permeability due to Pro substitutions may have resulted in stimulus-independent intralysosomal Ca2+ release, hence the surface expression and whole cell current of TRPML1. Indeed, surface staining of lysosome-associated membrane protein-1 (Lamp-1) was dramatically increased in cells expressing GOF TRPML1 channels. We conclude that TRPML1 is an inwardly rectifying, proton-impermeable, Ca2+ and Fe2+/Mn2+ dually permeable cation channel that may be gated by unidentified cellular mechanisms through a conformational change in the cytoplasmic face of the transmembrane 5 (TM5). Furthermore, activation of TRPML1 in LEL may lead to the appearance of TRPML1 proteins at the PM. The mucolipin TRP (TRPML) proteins are a family of endolysosomal cation channels with genetically established importance in humans and rodent. Mutations of human TRPML1 cause type IV mucolipidosis, a devastating pediatric neurodegenerative disease. Our recent electrophysiological studies revealed that, although a TRPML1-mediated current can only be recorded in late endosome and lysosome (LEL) using the lysosome patch clamp technique, a proline substitution in TRPML1 (TRPML1V432P) results in a large whole cell current. Thus, it remains unknown whether the large TRPML1V432P-mediated current results from an increased surface expression (trafficking), elevated channel activity (gating), or both. Here we performed systemic Pro substitutions in a region previously implicated in the gating of various 6 transmembrane cation channels. We found that several Pro substitutions displayed gain-of-function (GOF) constitutive activities at both the plasma membrane (PM) and endolysosomal membranes. Although wild-type TRPML1 and non-GOF Pro substitutions localized exclusively in LEL and were barely detectable in the PM, the GOF mutations with high constitutive activities were not restricted to LEL compartments, and most significantly, exhibited significant surface expression. Because lysosomal exocytosis is Ca2+-dependent, constitutive Ca2+ permeability due to Pro substitutions may have resulted in stimulus-independent intralysosomal Ca2+ release, hence the surface expression and whole cell current of TRPML1. Indeed, surface staining of lysosome-associated membrane protein-1 (Lamp-1) was dramatically increased in cells expressing GOF TRPML1 channels. We conclude that TRPML1 is an inwardly rectifying, proton-impermeable, Ca2+ and Fe2+/Mn2+ dually permeable cation channel that may be gated by unidentified cellular mechanisms through a conformational change in the cytoplasmic face of the transmembrane 5 (TM5). Furthermore, activation of TRPML1 in LEL may lead to the appearance of TRPML1 proteins at the PM." @default.
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- W2065524119 date "2009-11-01" @default.
- W2065524119 modified "2023-10-15" @default.
- W2065524119 title "Activating Mutations of the TRPML1 Channel Revealed by Proline-scanning Mutagenesis" @default.
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- W2065524119 cites W1968704909 @default.
- W2065524119 cites W1969515779 @default.
- W2065524119 cites W1973501614 @default.
- W2065524119 cites W1976255701 @default.
- W2065524119 cites W1976353035 @default.
- W2065524119 cites W1976411584 @default.
- W2065524119 cites W1976514154 @default.
- W2065524119 cites W1979123940 @default.
- W2065524119 cites W1983519301 @default.
- W2065524119 cites W1995692886 @default.
- W2065524119 cites W2000846031 @default.
- W2065524119 cites W2005505879 @default.
- W2065524119 cites W2009224366 @default.
- W2065524119 cites W2017593971 @default.
- W2065524119 cites W2021676916 @default.
- W2065524119 cites W2025102169 @default.
- W2065524119 cites W2025884071 @default.
- W2065524119 cites W2032776853 @default.
- W2065524119 cites W2033808333 @default.
- W2065524119 cites W2037307064 @default.
- W2065524119 cites W2037727418 @default.
- W2065524119 cites W2040664792 @default.
- W2065524119 cites W2050340611 @default.
- W2065524119 cites W2073189307 @default.
- W2065524119 cites W2079028379 @default.
- W2065524119 cites W2079823127 @default.
- W2065524119 cites W2097824035 @default.
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- W2065524119 cites W2108629058 @default.
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- W2065524119 cites W2150388442 @default.
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- W2065524119 doi "https://doi.org/10.1074/jbc.m109.037184" @default.
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