Plasma membrane biogenesis in the avian salt gland: a biochemical and quantitative electron microscopic autoradiographic study.
Plasma membrane biogenesis in the avian salt gland: a biochemical and quantitative electron microscopic autoradiographic study.
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鸟类盐腺质膜生物发生：生化和定量电子显微镜放射自显影研究。
DOI：
10.1002/aja.1001740105
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Hossler,FE
中科院分区：
文献类型：
--
作者：
SarrasJr,MP;Rosenzweig,LJ;Addis,JS;Hossler,FE
The avian salt gland provides an ideal system for the study of plasma membrane (PM) biogenesis. Feeding ducklings 1% sodium chloride (salt stress) induces the secretory cells of the gland to synthesize large amounts of PM, which forms an extensive basolateral PM domain after 7–9 days of treatment. In the present study, the initial biosynthetic events following salt stress were investigated.In vivostudies using3H‐uridine indicated that increased rates of RNA synthesis could be detected by 2 hr after the beginning of salt stress and continued through at least 12 hr. Underin vitroconditions, increased rates of protein and glycoprotein synthesis (as monitored by3H‐leucine and3H‐fucose incorporation, respectively) were also detected after 2 hr and continued through 7–9 days. Increased levels of Na, K‐ATPase, a specific secretory cell PM marker, were detected after 8 hr of treatment as monitored by specific activity and3H‐ouabain binding. Sodium dodecyl sulfate‐polyacryl‐amide slab gel electrophoresis coupled with fluorography indicated that both3H‐leucine and3H‐fucose were incorporated into partially purified preparations of Na, K‐ATPase isolated after 12 hr. Light microscopic autoradiographic analysis of pulse‐chase experiments indicated that in secretory cells of 12‐hr salt‐stressed glands,3H‐leucine‐ and3H‐fucose‐labelled products reached the cell periphery by 1–2 hr after the initial pulse. The incorporation of both tritiated precursors was predominately associated with the secretory cells. Quantitative electron microscopic autoradiography indicated that3H‐leucine is initially taken up by elements of the rough endoplasmic reticulum (RER) and cytoplasm (5 min postpulse), subsequently transported to and concentrated within components of the Golgi apparatus (10 min of chase), and ultimately incorporated into all domains of the plasma membrane of secretory cells by 1–2 hr of chase. The data is consistent with a flow of newly synthesized membrane components from RER to Golgi to plasma membrane and is analogous to the pattern previously found for the synthesis and processing of PM proteins in a wide variety of cell types.
