X-Ray Fluorescence Microscopy Reveals the Role of Selenium in Spermatogenesis |
| |
Authors: | Sebastian Kehr Lydia Finney Stefan Vogt Marina V. Kasaikina You Zhou Vadim N. Gladyshev |
| |
Affiliation: | 1 Redox Biology Center and Department of Biochemistry, University of Nebraska, Lincoln, NE 68588, USA 2 Biosciences Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA 3 X-ray Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA 4 Molecular Biology of Selenium Section, Laboratory of Cancer Prevention, CCR, NCI, NIH, Bethesda, MD 20892, USA 5 Center for Biotechnology, University of Nebraska, Lincoln, NE 68588, USA |
| |
Abstract: | Selenium (Se) is a trace element with important roles in human health. Several selenoproteins have essential functions in development. However, the cellular and tissue distribution of Se remains largely unknown because of the lack of analytical techniques that image this element with sufficient sensitivity and resolution. Herein, we report that X-ray fluorescence microscopy (XFM) can be used to visualize and quantify the tissue, cellular, and subcellular topography of Se. We applied this technique to characterize the role of Se in spermatogenesis and identified a dramatic Se enrichment specifically in late spermatids, a pattern that was not seen in any other elemental maps. This enrichment was due to elevated levels of the mitochondrial form of glutathione peroxidase 4 and was fully dependent on the supplies of Se by selenoprotein P. High-resolution scans revealed that Se concentrated near the lumen side of elongating spermatids, where structural components of sperm are formed. During spermatogenesis, maximal Se associated with decreased phosphorus, whereas Zn did not change. In sperm, Se was primarily in the midpiece and colocalized with Cu and Fe. XFM allowed quantification of Se in the midpiece (0.8 fg) and head (0.2 fg) of individual sperm cells, revealing the ability of sperm cells to handle the amounts of this element well above its toxic levels. Overall, the use of XFM allowed visualization of tissue and cellular Se and provided important insights in the role of this and other trace elements in spermatogenesis. |
| |
Keywords: | GPx4 or PHGPX, phospholipid hydroperoxide glutathione peroxidase mGPx4, mitochondrial GPx4 nGPx4, nuclear GPx4 Sec, selenocysteine PBS, phosphate-buffered saline PBST, phosphate-buffered saline with Tween SelP, selenoprotein P TGR, thioredoxin-glutathione reductase XFM, X-ray fluorescence microscopy |
本文献已被 ScienceDirect 等数据库收录! |
|