Scanning X-ray Microscopy of Living and Freeze-Dried Blood Cells in Two Vanadium-Rich Ascidian Species, Phallusia mammillata and Ascidia sydneiensis samea

Ueki Tatsuya

Takemoto Kuniko

Fayard Barbara

Salomé Murielle

Yamamoto Akitsugu

Kihara Hiroshi

Susini Jean

Scippa Silvia

Uyama Taro

Michibata Hitoshi

Zoological science

Some ascidians (sea squirts) accumulate the transitional metal vanadium in their blood cellsat concentrations of up to 350 mM, about 10 7 times its concentration found in seawater. There are approx-imately 10 different types of blood cell in ascidians. The identity of the true vanadium-containing blood cell(vanadocyte) is controversial and little is known about the subcellular distribution of vanadium. A scanningx-ray microscope installed at the ID21 beamline of the European Synchrotron Radiation Facility to visualizevanadium in ascidian blood cells. Without fixation, freezing or staining realized the visualization of vana-dium localized in living signet ring cells and vacuolated amoebocytes of two vanadium-rich ascidian spe-cies, Phallusia mammillata and Ascidia sydneiensis samea . A combination of transmission andfluorescence images of signet ring cells suggested that in both species the vacuoles contain vanadium.

vanadium

ascidians

vanadocytes

X-Ray microscopy

synchrotron radiation

Zoology [ 480 ]

eng

Zoological Society of Japan

[ISSN] 0289-0003

[NCID] AA10545874