A potential role for calcium / calmodulin-dependent protein kinase-related peptide in neuronal apoptosis: in vivo and in vitro evidence.
Previously, we have established that a product of the doublecortin-like kinase (DCLK) gene, DCLK-short, is cleaved by caspases during serum deprivation. Subsequently, the N-terminal cleavage product of DCLK-short facilitates apoptosis in the neuroblastoma cell line NG108. As this N-terminal cleavage product is highly homologous to calcium/calmodulin-dependent protein kinase-related peptide (CARP), another DCLK gene splice variant, we aimed to determine the possible apoptotic properties of CARP in vivo and in vitro. We report highly specific CARP expression in apoptotic granule cells in the rat dentate gyrus after adrenalectomy relative to healthy granule cells. CARP is significantly upregulated in the suprapyramidal blade of the dentate gyrus, with varying levels of upregulation, depending on the extent of adrenalectomy-induced apoptosis. Similar to the caspase-cleaved N-terminus of DCLK-short, CARP overexpression itself facilitated apoptosis in serum-deprived NG108 cells. Furthermore, CARP facilitated polymerization of tubulin in vitro and was capable of interacting with growth factor receptor-bound protein 2, an intracellular protein involved in vesicle trafficking. Together, our data demonstrate a facilitating role for CARP in the apoptotic process in granule cell populations sensitive to adrenalectomy, and suggest that this proapoptotic effect is mediated by increasing the stability of the microtubule cytoskeleton.
Division of Medical Pharmacology, Leiden/Amsterdam Centre for Drug Research, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands.
Geert J
GJ
Schenk
Bart
B
Engels
Yan-Ping
YP
Zhang
Carlos P
CP
Fitzsimons
Theo
T
Schouten
Marieke
M
Kruidering
E Ron
ER
de Kloet
Erno
E
Vreugdenhil
D000315:Adrenalectomy; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins / Q000502:physiology*; D019556:COS Cells; D045744:Cell Line, Tumor; D002522:Chlorocebus aethiops; D018891:Dentate Gyrus / Q000166:cytology / Q000502:physiology*; D000089662:Doublecortin Protein; D000089742:Doublecortin-Like Kinases; D004347:Drug Interactions; D051380:GRB2 Adaptor Protein / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D008845:Microinjections; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D011108:Polymers / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000008:administration & dosage / Q000494:pharmacology / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000494:pharmacology; D014404:Tubulin / Q000378:metabolism
D051017:Apoptosis Regulatory Proteins; C000714848:Dcx protein, rat; D000089662:Doublecortin Protein; D051380:GRB2 Adaptor Protein; D011108:Polymers; D011994:Recombinant Proteins; D014404:Tubulin; D000089742:Doublecortin-Like Kinases; C485526:Dclk1 protein, rat; D017346:Protein Serine-Threonine Kinases