Innovative TEM-coupled approaches to study foraminiferal cells

Transmission electron microscope (TEM) observation has revealed much about the basic cell biology of foraminifera. Yet, there remains much we do not know about foraminiferal cytology and physiology, especially for smaller benthic foraminifera, which inhabit a wide range of habitats. Recently, some TEM-coupled approaches have been developed to study correlative foraminiferal ecology and physiology in detail: Fluorescently Labeled Embedded Core (FLEC)-TEM for observing foraminiferal life-position together with their cytoplasmic ultrastructure, micro-X-ray computed tomography (CT)-TEM for observing and reconstructing foraminiferal cytoplasm in three dimensions (3D), and TEM-Nanometer-scale secondary ion mass spectrometry (NanoSIMS) for mapping of elemental and isotopic compositions at sub-micrometer resolutions with known ultrastructure. In this contribution, we review and illustrate these recent advances of TEM-coupled methods.