Lcb4p is a key regulator of ceramide synthesis from exogenous long chain sphingoid base in saccharomyces cerevisiae

Article Article scientifique Article Lcb4p is a key regulator of ceramide synthesis from exogenous long chain sphingoid base in saccharomyces cerevisiae eng 2003 author Funato Koichi 559478 author Lombardi Ruben author Vallee Béatrice Simone Renée An 559506 author Riezman Howard 134430 7325-7334 10.1074/jbc.M209925200 0021-9258 <p>Long chain sphingoid bases (LCBs) and their phosphates (LCBPs) are not only important intermediates in ceramide biosynthesis but also signaling molecules in the yeast, <i>Saccharomyces cerevisiae</i>. Their cellular levels, which control multiple cellular events in response to external and intrinsic signals, are tightly regulated by coordinated action of metabolic enzymes such as LCB kinase and LCBP phosphatase. However, little is known about the mechanisms by which the two enzymes generate biosynthetic or signaling outputs. It has been shown that the LCBP phosphatase, Lcb3p, is required for efficient ceramide synthesis from exogenous LCB. Here we present direct evidence that the major LCB kinase, Lcb4p, but not the minor kinase, Lcb5p, regulates synthesis of ceramide from exogenously added LCB. Surprisingly, our biochemical evidence suggests that the LCBP used for ceramide synthesis must be generated on the membrane. Our data show that Lcb4p is tightly associated with membranes and is localized to the endoplasmic reticulum where it can work in concert with Lcb3p. These results raise the conceptually attractive possibility that membrane-associated and cytosolic Lcb4p play distinct roles to differentially generate biosynthetic and signaling pools of LCBP.</p> Dewey 540 39 Département de biochimie 144 false The Journal of biological chemistry 278 9 78b33d03-75ca-4f53-9064-9dd0839cb5b7 Article (Published version) Public FUNATO_TJBC_73342003.pdf 1250948 application/pdf openAccess Faculté des sciences / Section de chimie et biochimie / Département de biochimie

Title	Published in	Year	Views	Downloads

Lcb4p is a key regulator of ceramide synthesis from exogenous long chain sphingoid base in saccharomyces cerevisiae	The Journal of biological chemistry	2003	183	71
Biosynthesis and trafficking of sphingolipids in the yeast Saccharomyces cerevisiae	Biochemistry	2002	539	0

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Funato, Koichi