PAFAH Ib phospholipase A(2) subunits have distinct roles in maintaining Golgi structure and function

作者：Bechler Marie E; Brown William J^*

来源：Biochimica et Biophysica Acta-Molecular and Cell Biology of Lipids, 2013, 1831(3): 595-601.

DOI：10.1016/j.bbalip.2012.12.004

• PLA(2)
• PAFAH Ib
• Golgi complex
• Secretory trafficking

Recent studies showed that the phospholipase subunits of Platelet Activating Factor Acetylhydrolase (PAFAH) Ib, alpha 1 and alpha 2 partially localize to the Golgi complex and regulate its structure and function. Using siRNA knockdown of individual subunits, we find that alpha 1 and alpha 2 perform overlapping and unique roles in regulating Golgi morphology, assembly, and secretory cargo trafficking. Knockdown of either alpha 1 or alpha 2 reduced secretion of soluble proteins, but neither single knockdown reduced secretion to the same degree as knockdown of both. Knockdown of alpha 1 or alpha 2 inhibited reassembly of an intact Golgi complex to the same extent as knockdown of both. Transport of VSV-G was slowed but at different steps in the secretory pathway: reduction of alpha 1 slowed trans Golgi network to plasma membrane transport, whereas alpha 2 loss reduced endoplasmic reticulum to Golgi trafficking. Similarly, knockdown of either subunit alone disrupted the Golgi complex but with markedly different morphologies. Finally, knockdown of alpha 1, or double knockdown of alpha 1 and alpha 2, resulted in a significant redistribution of kinase dead protein kinase D from the Golgi to the plasma membrane, whereas loss of alpha 2 alone had no such effect. These studies reveal an unexpected complexity in the regulation of Golgi structure and function by PAFAH Ib. This article is part of a Special Issue entitled Phospholipids and Phospholipid Metabolism.

• 出版日期2013-3