Abstract
Cyclin-dependent kinase 5 (Cdk5) is a proline-directed serine/threonine protein kinase that requires association with a regulatory protein, p35 or p39, to form an active enzyme. Munc18-1 plays an essential role in membrane fusion, and its function is regulated by phosphorylation. We report here that both p35 and p39 were expressed in insulin-secreting β-cells, where they exhibited individual subcellular distributions and associated with membranous organelles of different densities. Overexpression of Cdk5, p35, or p39 showed that Cdk5 and p39 augmented Ca2+-induced insulin exocytosis. Suppression of p39 and Cdk5, but not of p35, by antisense oligonucleotides selectively inhibited insulin exocytosis. Transient transfection of primary β-cells with Munc18-1 templates mutated in potential Cdk5 or PKC phosphorylation sites, in combination with Cdk5 and the different Cdk5 activators, suggested that Cdk5/p39-promoted Ca2+-dependent insulin secretion from primary β-cells by phosphorylating Munc18-1 at a biochemical step immediately prior to vesicle fusion.
| Original language | English |
|---|---|
| Pages (from-to) | 29534-29541 |
| Number of pages | 8 |
| Journal | Journal of Biological Chemistry |
| Volume | 279 |
| Issue number | 28 |
| DOIs | |
| State | Published - Jul 9 2004 |
| Externally published | Yes |
Fingerprint
ASJC Scopus subject areas
- Biochemistry
Cite this
Cyclin-dependent kinase 5 associated with p39 promotes Munc18-1 phosphorylation and Ca2+-dependent exocytosis. / Lilja, Lena; Johansson, Jenny Ulrika; Gromada, Jesper; Mandic, Slavena Andrea; Fried, Gabriel; Berggren, Per Olof; Bark, Christina.
In: Journal of Biological Chemistry, Vol. 279, No. 28, 09.07.2004, p. 29534-29541.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Cyclin-dependent kinase 5 associated with p39 promotes Munc18-1 phosphorylation and Ca2+-dependent exocytosis
AU - Lilja, Lena
AU - Johansson, Jenny Ulrika
AU - Gromada, Jesper
AU - Mandic, Slavena Andrea
AU - Fried, Gabriel
AU - Berggren, Per Olof
AU - Bark, Christina
PY - 2004/7/9
Y1 - 2004/7/9
N2 - Cyclin-dependent kinase 5 (Cdk5) is a proline-directed serine/threonine protein kinase that requires association with a regulatory protein, p35 or p39, to form an active enzyme. Munc18-1 plays an essential role in membrane fusion, and its function is regulated by phosphorylation. We report here that both p35 and p39 were expressed in insulin-secreting β-cells, where they exhibited individual subcellular distributions and associated with membranous organelles of different densities. Overexpression of Cdk5, p35, or p39 showed that Cdk5 and p39 augmented Ca2+-induced insulin exocytosis. Suppression of p39 and Cdk5, but not of p35, by antisense oligonucleotides selectively inhibited insulin exocytosis. Transient transfection of primary β-cells with Munc18-1 templates mutated in potential Cdk5 or PKC phosphorylation sites, in combination with Cdk5 and the different Cdk5 activators, suggested that Cdk5/p39-promoted Ca2+-dependent insulin secretion from primary β-cells by phosphorylating Munc18-1 at a biochemical step immediately prior to vesicle fusion.
AB - Cyclin-dependent kinase 5 (Cdk5) is a proline-directed serine/threonine protein kinase that requires association with a regulatory protein, p35 or p39, to form an active enzyme. Munc18-1 plays an essential role in membrane fusion, and its function is regulated by phosphorylation. We report here that both p35 and p39 were expressed in insulin-secreting β-cells, where they exhibited individual subcellular distributions and associated with membranous organelles of different densities. Overexpression of Cdk5, p35, or p39 showed that Cdk5 and p39 augmented Ca2+-induced insulin exocytosis. Suppression of p39 and Cdk5, but not of p35, by antisense oligonucleotides selectively inhibited insulin exocytosis. Transient transfection of primary β-cells with Munc18-1 templates mutated in potential Cdk5 or PKC phosphorylation sites, in combination with Cdk5 and the different Cdk5 activators, suggested that Cdk5/p39-promoted Ca2+-dependent insulin secretion from primary β-cells by phosphorylating Munc18-1 at a biochemical step immediately prior to vesicle fusion.
UR - http://www.scopus.com/inward/record.url?scp=3142660506&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=3142660506&partnerID=8YFLogxK
U2 - 10.1074/jbc.M312711200
DO - 10.1074/jbc.M312711200
M3 - Article
C2 - 15123626
AN - SCOPUS:3142660506
VL - 279
SP - 29534
EP - 29541
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 28
ER -