These neurons were derived from human embryonic stem cells. The neural cell bodies with axonal projections are visible in red, and the nuclei in blue. Some of the neurons have become dopaminergic neurons (yellow), the type that degenerate in people with Parkinson's disease. Image and caption information courtesy of the California Institute for Regenerative Medicine. Related to images 3270 and 3271.

This fused chromosome has two functional centromeres, shown as two sets of red and green dots. Centromeres are DNA/protein complexes that are key to splitting the chromosomes evenly during cell division. When dicentric chromosomes like this one are formed in a person, fertility problems or other difficulties may arise. Normal chromosomes carrying a single centromere (one set of red and green dots) are also visible in this image.

Three-dimensional reconstruction of a tubular matrix in a thin section of the peripheral endoplasmic reticulum between the plasma membranes of the cell.
The endoplasmic reticulum (ER) is a continuous membrane that extends like a net from the envelope of the nucleus outward to the cell membrane. The ER plays several roles within the cell, such as in protein and lipid synthesis and transport of materials between organelles.
Shown here are super-resolution microscopic images of the peripheral ER showing the structure of an ER tubular matrix between the plasma membranes of the cell. See image 5857 for a more detailed view of the area outlined in white in this image. For another view of the ER tubular matrix see image 5855

This image of human red blood cells was obtained with the help of a scanning electron microscope, an instrument that uses a finely focused electron beam to yield detailed images of the surface of a sample.

Yeast cells with endocytic actin patches (green). These patches help cells take in outside material. When a cell is in interphase, patches concentrate at its ends. During later stages of cell division, patches move to where the cell splits. This image was captured using wide-field microscopy with deconvolution.

Related to images 6791, 6792, 6794, 6797, 6798, and videos 6795 and 6796.

Cell-like compartments spontaneously emerge from scrambled frog eggs, with nuclei (blue) from frog sperm. Endoplasmic reticulum (red) and microtubules (green) are also visible. Regions without nuclei formed smaller compartments. Video created using epifluorescence microscopy.

For more photos of cell-like compartments from frog eggs view: 6584, 6585, 6586, 6591, 6592, and 6593.

For videos of cell-like compartments from frog eggs view: 6587, 6589, and 6590.

On the left, the boundary of a breast tumor (yellow) attaches to collagen fibers that are closest to it (green) using DDR2. On the right, a tumor without DDR2 remains disconnected from the collagen.

A peripheral nerve cell made from human embryonic stem cell-derived neural crest stem cells. The nucleus is shown in blue, and nerve cell proteins peripherin and beta-tubulin (Tuj1) are shown in green and red, respectively. Related to image 3263.

Misfolded proteins (green) within mitochondria (red). Related to video 5877.

The green spots in this image are clumps of protein inside yeast cells that are deficient in both zinc and a protein called Tsa1 that prevents clumping. Protein clumping plays a role in many diseases, including Parkinson's and Alzheimer's, where proteins clump together in the brain. Zinc deficiency within a cell can cause proteins to mis-fold and eventually clump together. Normally, in yeast, Tsa1 codes for so-called "chaperone proteins" which help proteins in stressed cells, such as those with a zinc deficiency, fold correctly. The research behind this image was published in 2013 in the Journal of Biological Chemistry.

Hydra magnipapillata is an invertebrate animal used as a model organism to study developmental questions, for example the formation of the body axis.

Cancer cells can change their migration phenotype, which includes their shape and the way that they move to invade different tissues. This movie shows breast cancer cells forming a tumor spheroid—a 3D ball of cancer cells—and invading the surrounding tissue. Images were taken using a laser scanning confocal microscope, and artificial intelligence (AI) models were used to segment and classify the images by migration phenotype. On the right side of the video, each phenotype is represented by a different color, as recognized by the AI program based on identifiable characteristics of those phenotypes. The movie demonstrates how cancer cells can use different migration modes during growth and metastasis—the spreading of cancer cells within the body.

A cell in prophase, near the start of mitosis: In the nucleus, chromosomes condense and become visible. In the cytoplasm, the spindle forms. Mitosis is responsible for growth and development, as well as for replacing injured or worn out cells throughout the body. For simplicity, mitosis is illustrated here with only six chromosomes.

Astrocytes in the cross section of a human optic nerve head

Multiphoton fluorescence image of HeLa cells with cytoskeletal microtubules (magenta) and DNA (cyan). Nikon RTS2000MP custom laser scanning microscope. See related images 3518, 3519, 3521, 3522.

During cell division, spindle pole bodies (glowing dots) move toward the ends of yeast cells to separate copied genetic information. Contractile rings (glowing bands) form in cells’ middles and constrict to help them split. This time-lapse video was captured using wide-field microscopy with deconvolution.

Related to images 6791, 6792, 6793, 6794, 6797, 6798, and video 6795.

The nucleus of a degenerating human tendon cell, also known as a tenocyte. It has been color-coded based on the density of chromatin—a substance made up of DNA and proteins. Areas of low chromatin density are shown in blue, and areas of high chromatin density are shown in red. This image was captured using Stochastic Optical Reconstruction Microscopy (STORM).

Related to images 6887 and 6888.

The worm Caenorhabditis elegans is a popular laboratory animal because its small size and fairly simple body make it easy to study. Scientists use this small worm to answer many research questions in developmental biology, neurobiology, and genetics. This image, which was taken with transmission electron microscopy (TEM), shows a cross-section through C. elegans, revealing various internal structures.

The image is from a figure in an article published in the journal eLife. There is an annotated version of this graphic at 5760.

Like a major city, a cell teems with specialized workers that carry out its daily operations--making energy, moving proteins, or helping with other tasks. Researchers took microscopic pictures of thin layers of a cell and then combined them to make this 3-D image featuring color-coded organelles--the cell's "workers." Using this image, scientists can understand how these specialized components fit together in the cell's packed inner world.

Cdc42, a member of the Rho family of small guanosine triphosphatase (GTPase) proteins, regulates multiple cell functions, including motility, proliferation, apoptosis, and cell morphology. In order to fulfill these diverse roles, the timing and location of Cdc42 activation must be tightly controlled. Klaus Hahn and his research group use special dyes designed to report protein conformational changes and interactions, here in living neutrophil cells. Warmer colors in this image indicate higher levels of activation. Cdc42 looks to be activated at cell protrusions.

Related to images 2452, 2453, and 2454.

A section of mouse colon with gut bacteria (center, in green) residing within a protective pocket. Understanding how microorganisms colonize the gut could help devise ways to correct for abnormal changes in bacterial communities that are associated with disorders like inflammatory bowel disease.

The nucleus of a human fibroblast cell with chromatin—a substance made up of DNA and proteins—shown in various colors. Fibroblasts are one of the most common types of cells in mammalian connective tissue, and they play a key role in wound healing and tissue repair. This image was captured using Stochastic Optical Reconstruction Microscopy (STORM).

Related to images 6887 and 6893.

Bean-shaped mitochondria are cells' power plants. These organelles have their own DNA and replicate independently. The highly folded inner membranes are the site of energy generation.

Hippocampal neuron from rodent brain with dendrites shown in blue. The hundreds of tiny magenta, green and white dots are the dendritic spines of excitatory synapses.

Multiple actin filaments (magenta) are organized around a dynamin helical polymer (rainbow colored) in this model derived from cryo-electron tomography. By bundling actin, dynamin increases the strength of a cell’s skeleton and plays a role in cell-cell fusion, a process involved in conception, development, and regeneration.

The worm Caenorhabditis elegans is a popular laboratory animal because its small size and fairly simple body make it easy to study. Scientists use this small worm to answer many research questions in developmental biology, neurobiology, and genetics. This image, which was taken with transmission electron microscopy (TEM), shows a cross-section through C. elegans, revealing various internal structures labeled in the image. You can find a high-resolution image without the annotations at image 5759.

The image is from a figure in an article published in the journal eLife.

A mouse's fat cells (red) are shown surrounded by a network of blood vessels (green). Fat cells store and release energy, protect organs and nerve tissues, insulate us from the cold, and help us absorb important vitamins.

This image was part of the Life: Magnified exhibit that ran from June 3, 2014, to January 21, 2015, at Dulles International Airport.

It has been said that gastrulation is the most important event in a person's life. This part of early embryonic development transforms a simple ball of cells and begins to define cell fate and the body axis. In a study published in Science magazine in March 2012, NIGMS grantee Bob Goldstein and his research group studied how contractions of actomyosin filaments in C. elegans and Drosophila embryos lead to dramatic rearrangements of cell and embryonic structure. This research is described in detail in the following article: "Triggering a Cell Shape Change by Exploiting Preexisting Actomyosin Contractions." In these images, myosin (green) and plasma membrane (red) are highlighted at four timepoints in gastrulation in the roundworm C. elegans. The blue highlights in the top three frames show how cells are internalized, and the site of closure around the involuting cells is marked with an arrow in the last frame. See related video 3334.

This human T cell (blue) is under attack by HIV (yellow), the virus that causes AIDS. The virus specifically targets T cells, which play a critical role in the body's immune response against invaders like bacteria and viruses.

This image was part of the Life: Magnified exhibit that ran from June 3, 2014, to January 21, 2015, at Dulles International Airport.

The feeding tube, or pharynx, of a planarian worm with cilia shown in red and muscle fibers shown in green

Cells walk along body surfaces via tiny "feet," called focal adhesions, that connect with the extracellular matrix. See image 2503 for a labeled version of this illustration.

Borrelia burgdorferi is a spirochete, a class of long, slender bacteria that typically take on a coiled shape. Infection with this bacterium causes Lyme disease.

Two highly stressed osteosarcoma cells are shown with a set of green droplet-like structures followed by a second set of magenta droplets. These droplets are composed of fluorescently labeled stress-response proteins, either G3BP or UBQLN2 (Ubiquilin-2). Each protein is undergoing a fascinating process, called phase separation, in which a non-membrane bound compartment of the cytoplasm emerges with a distinct environment from the surrounding cytoplasm. Subsequently, the proteins fuse with like proteins to form larger droplets, in much the same way that raindrops merge on a car’s windshield.

The photo shows a confocal microscopy image of perineuronal nets (PNNs), which are specialized extracellular matrix (ECM) structures in the brain. The PNN surrounds some nerve cells in brain regions including the cortex, hippocampus and thalamus. Researchers study the PNN to investigate their involvement stabilizing the extracellular environment and forming nets around nerve cells and synapses in the brain. Abnormalities in the PNNs have been linked to a variety of disorders, including epilepsy and schizophrenia, and they limit a process called neural plasticity in which new nerve connections are formed. To visualize the PNNs, researchers labeled them with Wisteria floribunda agglutinin (WFA)-fluorescein. Related to image 3741.

Living primary mouse embryonic fibroblasts. Mitochondria (green) stained with the mitochondrial membrane potential indicator, rhodamine 123. Nuclei (blue) are stained with DAPI. Caption from a November 26, 2012 news release from U Penn (Penn Medicine).

This video results from a research project to visualize which regions of the adult fruit fly (Drosophila) brain derive from each neural stem cell. First, researchers collected several thousand fruit fly larvae and fluorescently stained a random stem cell in the brain of each. The idea was to create a population of larvae in which each of the 100 or so neural stem cells was labeled at least once. When the larvae grew to adults, the researchers examined the flies’ brains using confocal microscopy. With this technique, the part of a fly’s brain that derived from a single, labeled stem cell “lights up.” The scientists photographed each brain and digitally colorized its lit-up area. By combining thousands of such photos, they created a three-dimensional, color-coded map that shows which part of the Drosophila brain comes from each of its ~100 neural stem cells. In other words, each colored region shows which neurons are the progeny or “clones” of a single stem cell. This work established a hierarchical structure as well as nomenclature for the neurons in the Drosophila brain. Further research will relate functions to structures of the brain.

Related to images 5838 and 5868.

The 3D single-molecule super-resolution reconstruction of the entire nuclear lamina in a HeLa cell was acquired using the TILT3D platform. TILT3D combines a tilted light sheet with point-spread function (PSF) engineering to provide a flexible imaging platform for 3D single-molecule super-resolution imaging in mammalian cells.
See 6573 for 3 separate views of this structure.

A sensor particle being engulfed by a macrophage—an immune cell—and encapsuled in a compartment called a phagosome. The phagosome then fuses with lysosomes—another type of compartment. The left video shows snowman-shaped sensor particles with fluorescent green nanoparticle “heads” and “bodies” colored red by Förster Resonance Energy Transfer (FRET)-donor fluorophores. The middle video visualizes light blue FRET signals that are only generated when the “snowman” sensor—the FRET-donor—fuses with the lysosomes, which are loaded with FRET-acceptors. The right video combines the other two. The videos were captured using epi-fluorescence microscopy.

More details can be found in the paper “Transport motility of phagosomes on actin and microtubules regulates timing and kinetics of their maturation” by Yu et al.

Influenza (flu) virus proteins in the act of self-replication. Viral nucleoprotein (blue) encapsidates [encapsulates] the RNA genome (green). The influenza virus polymerase (orange) reads and copies the RNA genome. In the background is an image of influenza virus ribonucleoprotein complexes observed using cryo-electron microscopy. This image is from a November 2012 News Release.

Cell-like compartments that spontaneously emerged from scrambled frog eggs. Endoplasmic reticulum (red) and microtubules (green) are visible. Image created using epifluorescence microscopy.

For more photos of cell-like compartments from frog eggs view: 6584, 6585, 6591, 6592, and 6593.

For videos of cell-like compartments from frog eggs view: 6587, 6588, 6589, and 6590.

A light microscope image of a cell from the endosperm of an African globe lily (Scadoxus katherinae). This is one frame of a time-lapse sequence that shows cell division in action. The lily is considered a good organism for studying cell division because its chromosomes are much thicker and easier to see than human ones. Staining shows microtubules in red and chromosomes in blue. Here, condensed chromosomes are clearly visible and are starting to separate to form two new cells.

A light microscope image of cells from the endosperm of an African globe lily (Scadoxus katherinae). This is one frame of a time-lapse sequence that shows cell division in action. The lily is considered a good organism for studying cell division because its chromosomes are much thicker and easier to see than human ones. Staining shows microtubules in red and chromosomes in blue. Here, condensed chromosomes are clearly visible and have separated into the opposite sides of a dividing cell.

Related to images 1010, 1012, 1013, 1014, 1015, 1016, 1017, 1018, 1019, and 1021.

Staphylococcus aureus bacteria (green) grouping together upon contact with synovial fluid—a viscous substance found in joints. The formation of groups can help protect the bacteria from immune system defenses and from antibiotics, increasing the likelihood of an infection. This video is a 1-hour time lapse and was captured using a confocal laser scanning microscope.

More information about the research that produced this video can be found in the Journal of Bacteriology paper "In Vitro Staphylococcal Aggregate Morphology and Protection from Antibiotics Are Dependent on Distinct Mechanisms Arising from Postsurgical Joint Components and Fluid Motion" by Staats et al.

Related to images 6803 and 6804.

In this image, viewed with a ZEISS ORION NanoFab microscope, the community of cells lining a mouse airway is magnified more than 10,000 times. This collection of cells, known as the mucociliary escalator, is also found in humans. It is our first line of defense against inhaled bacteria, allergens, pollutants, and debris. Malfunctions in the system can cause or aggravate lung infections and conditions such as asthma and chronic obstructive pulmonary disease. The cells shown in gray secrete mucus, which traps inhaled particles. The colored cells sweep the mucus layer out of the lungs.

This image was part of the Life: Magnified exhibit that ran from June 3, 2014, to January 21, 2015, at Dulles International Airport.

A light microscope image of a cell from the endosperm of an African globe lily (Scadoxus katherinae). This is one frame of a time-lapse sequence that shows cell division in action. The lily is considered a good organism for studying cell division because its chromosomes are much thicker and easier to see than human ones. Staining shows microtubules in red and chromosomes in blue. Here, condensed chromosomes are clearly visible and are separating to form the cores of two new cells.

Related to images 1011, 1012, 1013, 1014, 1015, 1016, 1017, 1018, 1019, and 1021.

3D image of Caulobacter bacterium with various components highlighted: cell membranes (red and blue), protein shell (green), protein factories known as ribosomes (yellow), and storage granules (orange).

Cdc42, a member of the Rho family of small guanosine triphosphatase (GTPase) proteins, regulates multiple cell functions, including motility, proliferation, apoptosis, and cell morphology. In order to fulfill these diverse roles, the timing and location of Cdc42 activation must be tightly controlled. Klaus Hahn and his research group use special dyes designed to report protein conformational changes and interactions, here in living neutrophil cells. Warmer colors in this image indicate higher levels of activation. Cdc42 looks to be activated at cell protrusions.

Related to images 2451, 2453, and 2454.

Like a paint-by-numbers picture, painted probes tint individual human chromosomes by targeting specific DNA sequences. Chromosome 13 is colored green, chromosome 14 is in red and chromosome 15 is painted yellow. The image shows two examples of fused chromosomes—a pair of chromosomes 15 connected head-to-head (yellow dumbbell-shaped structure) and linked chromosomes 13 and 14 (green and red dumbbell). These fused chromosomes—called dicentric chromosomes—may cause fertility problems or other difficulties in people.