Suppression of the expression of a pancreatic beta-cell form of the kinesin heavy chain by antisense oligonucleotides inhibits insulin secretion from primary cultures of mouse beta-cells.
Granular/vesicular transport is thought to be supported by microtubule-based force-generating adenosine triphosphatases such as kinesin. Kinesin is a motor molecule that has been well studied in brain and other neuronal tissues. Although vesicular transport is important for pancreatic beta-cell secretory activities, the role of kinesin in beta-cell function has not been investigated. It is hypothesized that kinesin functions as a translocator that associates with both microtubules and insulin-containing granules in beta-cells and transports the secretory granules from deep within the cytoplasm, where insulin is synthesized and processed, to the surface of beta-cells upon secretory stimulation. To test this hypothesis, a mouse beta-cell kinesin heavy chain complementary DNA was cloned and sequenced. Kinesin expression in primary cultures of mouse beta-cells then was selectively suppressed by antimouse beta-cell kinesin heavy chain antisense oligonucleotide treatment. Analysis of insulin secretion determined that the basal level of insulin secretion from the treated cells was decreased by 50%. Furthermore, glucose-stimulated insulin release from treated beta-cells was reduced by almost 70% after suppression of kinesin expression by antisense treatment. The findings from this study provide the first direct evidence that kinesin, a microtubule-based motor protein, plays an important role in insulin secretion.
Meng
Y X
YX
Department of Structural and Cellular Biology, University of South Alabama, Mobile 36688, USA.
Wilson
G W
GW
Avery
M C
MC
Varden
C H
CH
Balczon
R
R
D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D018076:DNA, Complementary / Q000302:isolation & purification; D015870:Gene Expression / Q000187:drug effects*; D005947:Glucose / Q000494:pharmacology; D007328:Insulin / Q000096:biosynthesis / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000201:enzymology* / Q000378:metabolism* / Q000648:ultrastructure; D016547:Kinesins / Q000235:genetics*; D051379:Mice; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D016376:Oligonucleotides, Antisense / Q000378:metabolism / Q000494:pharmacology*
D018076:DNA, Complementary; D007328:Insulin; D016376:Oligonucleotides, Antisense; D016547:Kinesins; D005947:Glucose