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. 2012 Jun 22;3(8):618–626. doi: 10.1007/s13238-012-2938-0

Bulk-like endocytosis plays an important role in the recycling of insulin granules in pancreatic beta cells

Du Wen 1,4, Yanhong Xue 1,4, Kuo Liang 3, Tianyi Yuan 2, Jingze Lu 1, Wei Zhao 1,4, Tao Xu 1,✉, Liangyi Chen 2,✉
PMCID: PMC4875361  PMID: 22729398

Abstract

Although bulk endocytosis has been found in a number of neuronal and endocrine cells, the molecular mechanism and physiological function of bulk endocytosis remain elusive. In pancreatic beta cells, we have observed bulk-like endocytosis evoked both by flash photolysis and trains of depolarization. Bulk-like endocytosis is a clathrin-independent process that is facilitated by enhanced extracellular Ca2+ entry and suppressed by the inhibition of dynamin function. Moreover, defects in bulk-like endocytosis are accompanied by hyperinsulinemia in primary beta cells dissociated from diabetic KKAy mice, which suggests that bulk-like endocytosis plays an important role in maintaining the exo-endocytosis balance and beta cell secretory capability.

Keywords: bulk-like endocytosis, clathrin-independent endocytosis, dynamin, diabetic KKAy mice

Contributor Information

Tao Xu, Email: xutao@ibp.ac.cn.

Liangyi Chen, Email: lychen@pku.edu.cn.

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