Related Experiment Video
Updated: Aug 6, 2026

Coculture Analysis of Extracellular Protein Interactions Affecting Insulin Secretion by Pancreatic Beta Cells
Published on: June 15, 2013
Kinectin participates in microtubule-dependent hormone secretion in pancreatic islet beta-cells
Ji-Zhong Bai1, Yu Mon, Geoffrey W Krissansen
1Department of Molecular Medicine & Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
Abstract:
Kinectin (KNT) is a candidate membrane receptor for kinesin in the movement of intracellular organelles along microtubules. Isoforms of KNT exist containing different combinations of six small (residues 23-33) variable domains (vd) vd1-6 within the C-terminus. Here we investigate a role for KNT and its isoform KNTvd4(-) in the transport of amylin and insulin-containing secretory vesicles in the pancreatic islet beta-cell line RINm5F. KNTvd4(-) lacks vd4 that forms the kinesin-binding domain, and hence its role in the cell is an enigma. We report that amylin-containing vesicles also contained insulin, and exhibited microtubule, and small G-protein-dependent secretion. Knockdown of KNT by small interference RNA (siRNA) inhibited amylin expression and secretion. In contrast, recombinant KNTvd4(-) overexpressed in RINm5F cells associated with amylin-containing vesicles and inhibited amylin secretion, but had no discernible affect on amylin expression. The data suggests that both KNT and KNTvd4(-) participate in microtubule-dependent secretion of amylin in islet beta-cells.
Related Concept Videos
Insulin Secretory Vesicles
Glucose Homeostasis: Pancreatic Islets and Insulin Secretion
Insulin and C-peptide are co-secreted in...
Overview of Secretory Vesicles
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Cells and Secretions of the Pancreas
Exocrine function is carried out by acinar cells, organized into clusters known as acini. These cells contribute to digestion by releasing substantial quantities of enzyme-rich, alkaline digestive juices.
Concurrently, the dispersed clusters of endocrine cells throughout the...
Insulin: The Receptor and Signaling Pathways
Hormones Regulating Blood Glucose
In addition to accelerating glucose uptake and utilization, insulin has...

