Chromogranin B-induced secretory granule biogenesis: comparison with the similar role of chromogranin A |
| |
Authors: | Huh Yang Hoon Jeon Soung Hoo Yoo Seung Hyun |
| |
Affiliation: | Department of Biochemistry, Inha University College of Medicine, Jung Gu, Incheon 400-712, Korea. |
| |
Abstract: | The two major proteins of secretory granules of secretory cells, chromogranins A (CGA) and B (CGB), have previously been proposed to play key roles in secretory granule biogenesis. Recently, CGA was reported to play an on/off switch role for secretory granule biogenesis. In the present study we found CGB being more effective than CGA in inducing secretory granule formation in non-neuroendocrine NIH3T3 and COS-7 cells. The mean number of dense core granules formed/cell of CGA-transfected NIH3T3 cells was 2.51, whereas that of CGB-transfected cells was 4.02, indicating the formation of 60% more granules in the CGB-transfected cells. Similarly, there were 55% more dense core granules formed in the CGB-transfected COS-7 cells than in the CGA-transfected cells. Moreover, transfection of CGA- and CGB-short interfering RNA (siRNA) into neuroendocrine PC12 cells not only decreased the amount of CGA and CGB expressed but also reduced the number of secretory granules by 41 and 78%, respectively, further suggesting the importance of CGB expression in secretory granule formation. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|