This 2-hour-old fly embryo already has a blueprint for its formation, and the process for following it is so precise that the difference of just a few key molecules can change the plans. Here, blue marks a high concentration of Bicoid, a key signaling protein that directs the formation of the fly's head. It also regulates another important protein, Hunchback (green), that further maps the head and thorax structures and partitions the embryo in half (red is DNA). The yellow dots overlaying the embryo plot the concentration of Bicoid versus Hunchback proteins within each nucleus. The image illustrates the precision with which an embryo interprets and locates its halfway boundary, approaching limits set by simple physical principles. This image was a finalist in the 2008 Drosophila Image Award.

Collecting and transporting cellular waste and sorting it into recylable and nonrecylable pieces is a complex business in the cell. One key player in that process is the endosome, which helps collect, sort and transport worn-out or leftover proteins with the help of a protein assembly called the endosomal sorting complexes for transport (or ESCRT for short). These complexes help package proteins marked for breakdown into intralumenal vesicles, which, in turn, are enclosed in multivesicular bodies for transport to the places where the proteins are recycled or dumped. In this image, a multivesicular body (the round structure slightly to the right of center) contain tiny intralumenal vesicles (with a diameter of only 25 nanometers; the round specks inside the larger round structure) adjacent to the cell's vacuole (below the multivesicular body, shown in darker and more uniform gray).

Scientists working with baker's yeast (Saccharomyces cerevisiae) study the budding inward of the limiting membrane (green lines on top of the yellow lines) into the intralumenal vesicles. This tomogram was shot with a Tecnai F-20 high-energy electron microscope, at 29,000x magnification, with a 0.7-nm pixel, ~4-nm resolution.

To learn more about endosomes, see the Biomedical Beat blog post The Cell’s Mailroom. Related to a color-enhanced version 5767 and image 5769.

A protein called tubulin (green) accumulates in the center of a nucleus (outlined in pink) from an aging cell. Normally, this protein is kept out of the nucleus with the help of gatekeepers known as nuclear pore complexes. But NIGMS-funded researchers found that wear and tear to long-lived components of the complexes eventually lowers the gatekeepers' guard. As a result, cytoplasmic proteins like tubulin gain entry to the nucleus while proteins normally confined to the nucleus seep out. The work suggests that finding ways to stop the leakage could slow the cellular aging process and possibly lead to new therapies for age-related diseases.

A three-dimensional representation of the structure of E2, a key antigen protein involved with hepatitis C virus infection.

A shell from the venomous cone snail Conus omaria, which lives in the Pacific and Indian oceans and eats other snails. University of Utah scientists discovered a new toxin in this snail species' venom, and say it will be a useful tool in designing new medicines for a variety of brain disorders, including Alzheimer's and Parkinson's diseases, depression, nicotine addiction and perhaps schizophrenia.

These mitochondria (red) are from the heart muscle cell of a rat. Mitochondria have an inner membrane that folds in many places (and that appears here as striations). This folding vastly increases the surface area for energy production. Nearly all our cells have mitochondria. Related to image 3664.

The receptor is shown bound to an inverse agonist, doxepin.

In many animals, the egg cell develops alongside sister cells. These sister cells are called nurse cells in the fruit fly (Drosophila melanogaster), and their job is to “nurse” an immature egg cell, or oocyte. Toward the end of oocyte development, the nurse cells transfer all their contents into the oocyte in a process called nurse cell dumping. This process involves significant shape changes on the part of the nurse cells (blue), which are powered by wavelike activity of the protein myosin (red). This image was captured using a confocal laser scanning microscope. Related to video 6754.

Developing fruit fly spermatids require caspase activity (green) for the elimination of unwanted organelles and cytoplasm via apoptosis.

When the heat shock protein hsp33 is folded, it is inactive and contains a zinc ion, stabilizing the redox sensitive domain (orange). In the presence of an environmental stressor, the protein releases the zinc ion, which leads to the unfolding of the redox domain. This unfolding causes the chaperone to activate by reaching out its "arm" (green) to protect other proteins.

A computer model shows how the endoplasmic reticulum is close to and almost wraps around mitochondria in the cell. The endoplasmic reticulum is lime green and the mitochondria are yellow. This image relates to a July 27, 2009 article in Computing Life.

This sculpture made of purple and clear glass beads depicts bacteriophage Phi174, a virus that infects bacteria. It rests on a surface that portrays an adaptive landscape, a conceptual visualization. The ridges represent the gene combinations associated with the greatest fitness levels of the virus, as measured by how quickly the virus can reproduce itself. Phi174 is an important model system for studies of viral evolution because its genome can readily be sequenced as it evolves under defined laboratory conditions.

A scanning electron microscope picture of a nerve ending. It has been broken open to reveal vesicles (orange and blue) containing chemicals used to pass messages in the nervous system.

This video shows the structure of the pore-forming protein VDAC-1 from humans. This molecule mediates the flow of products needed for metabolism--in particular the export of ATP--across the outer membrane of mitochondria, the power plants for eukaryotic cells. VDAC-1 is involved in metabolism and the self-destruction of cells--two biological processes central to health.

Related to videos 2571 and 2572.

Each of the colored specs in this image is a cell on the surface of a fish scale. To better understand how wounds heal, scientists have inserted genes that make cells brightly glow in different colors into the skin cells of zebrafish, a fish often used in laboratory research. The colors enable the researchers to track each individual cell, for example, as it moves to the location of a cut or scrape over the course of several days. These technicolor fish endowed with glowing skin cells dubbed "skinbow" provide important insight into how tissues recover and regenerate after an injury.

For more information on skinbow fish, see the Biomedical Beat blog post Visualizing Skin Regeneration in Real Time and a press release from Duke University highlighting this research. Related to image 3783.

As an egg cell develops, a process called polarization controls what parts ultimately become the embryo's head and tail. This picture shows an egg of the fruit fly Drosophila. Red and green mark two types of signaling proteins involved in polarization. Disrupting these signals can scramble the body plan of the embryo, leading to severe developmental disorders.

An image of the area of the mouse brain that serves as the 'master clock,' which houses the brain's time-keeping neurons. The nuclei of the clock cells are shown in blue. A small molecule called VIP, shown in green, enables neurons in the central clock in the mammalian brain to synchronize.

Opioid receptors on the surfaces of brain cells are involved in pleasure, pain, addiction, depression, psychosis, and other conditions. The receptors bind to both innate opioids and drugs ranging from hospital anesthetics to opium. Researchers at The Scripps Research Institute, supported by the NIGMS Protein Structure Initiative, determined the first three-dimensional structure of a human opioid receptor, a kappa-opioid receptor. In this illustration, the submicroscopic receptor structure is shown while bound to an agonist (or activator). The structure is superimposed on a poppy flower, the source of opium.

CellPack image of the H1N1 influenza virus, with hemagglutinin and neuraminidase glycoproteins in green and red, respectively, on the outer envelope (white); matrix protein in gray, and ribonucleoprotein particles inside the virus in red and green. Related to image 6356.

A humorous treatment of the concept of a cycling cell.

A rendering of an activity biosensor image overlaid with a cell-centered frame of reference used for image analysis of signal transduction. This is an example of NIH-supported research on single-cell analysis. Related to 2798 , 2799, 2800, 2801 and 2803.

Bioengineers were able to coax bacteria to blink in unison on microfluidic chips. This image shows a small chip with about 500 blinking bacterial colonies or biopixels. Related to images 3265 and 3268. From a UC San Diego news release, "Researchers create living 'neon signs' composed of millions of glowing bacteria."

The nuclei stained green highlight human embryonic stem cells grown under controlled conditions in a laboratory. Blue represents the DNA of surrounding, supportive feeder cells. Image and caption information courtesy of the California Institute for Regenerative Medicine. See related image 3724.

Model based on X-ray crystallography of the structure of a small heat shock protein complex from the bacteria, Methanococcus jannaschii. Methanococcus jannaschii is an organism that lives at near boiling temperature, and this protein complex helps it cope with the stress of high temperature. Similar complexes are produced in human cells when they are "stressed" by events such as burns, heart attacks, or strokes. The complexes help cells recover from the stressful event.

The structure of the pore-forming protein VDAC-1 from humans. This molecule mediates the flow of products needed for metabolism--in particular the export of ATP--across the outer membrane of mitochondria, the power plants for eukaryotic cells. VDAC-1 is involved in metabolism and the self-destruction of cells--two biological processes central to health.

Related to images 2494, 2495, and 2488.

Hippocampal cells in culture with a neuron in green, showing hundreds of the small protrusions known as dendritic spines. The dendrites of other neurons are labeled in blue, and adjacent glial cells are shown in red.

HIV is a retrovirus, a type of virus that carries its genetic material not as DNA but as RNA. Long before anyone had heard of HIV, researchers in labs all over the world studied retroviruses, tracing out their life cycle and identifying the key proteins the viruses use to infect cells. When HIV was identified as a retrovirus, these studies gave AIDS researchers an immediate jump-start. The previously identified viral proteins became initial drug targets. See images 2514 and 2515 for labeled versions of this illustration. Featured in The Structures of Life.

CCD-1 is an enzyme produced by the bacterium Clostridioides difficile that helps it resist antibiotics. Using X-ray crystallography, researchers determined the structure of a complex between CCD-1 and the antibiotic cefotaxime (purple, yellow, and blue molecule). The structure revealed that CCD-1 provides extensive hydrogen bonding (shown as dotted lines) and stabilization of the antibiotic in the active site, leading to efficient degradation of the antibiotic.

Related to images 6764, 6765, and 6766.

The two large, central, round shapes are ovaries from a typical fruit fly (Drosophila melanogaster). The small butterfly-like structures surrounding them are fruit fly ovaries where researchers suppressed the expression of a gene that controls microtubule polymerization and is necessary for normal development. This image was captured using a confocal laser scanning microscope.

Related to image 6807.

Cell mopping up.

The world's smallest motor, ATP synthase, generates energy for the cell. See image 2517 for an unlabeled version of this illustration. Featured in The Chemistry of Health.

Cells move forward with lamellipodia and filopodia supported by networks and bundles of actin filaments. Proper, controlled cell movement is a complex process. Recent research has shown that an actin-polymerizing factor called the Arp2/3 complex is the key component of the actin polymerization engine that drives amoeboid cell motility. ARPC3, a component of the Arp2/3 complex, plays a critical role in actin nucleation. In this photo, the ARPC3+/+ fibroblast cells were fixed and stained with Alexa 546 phalloidin for F-actin (red), mDia1 (green), and DAPI to visualize the nucleus (blue). mDia1 is localized at the lamellipodia of ARPC3+/+ fibroblast cells. Related to images 3328, 3329, 3331, 3332, and 3333.

Map of microtubule growth rates. Rates are color coded. This is an example of NIH-supported research on single-cell analysis. Related to 2798 , 2799, 2801, 2802 and 2803.

You are face to face with a 6-day-old zebrafish larva. What look like eyes will become nostrils, and the bulges on either side will become eyes. Scientists use fast-growing, transparent zebrafish to see body shapes form and organs develop over the course of just a few days. Images like this one help researchers understand how gene mutations can lead to facial abnormalities such as cleft lip and palate in people.

This image won a 2016 FASEB BioArt award. In addition, NIH Director Francis Collins featured this on his blog on January 26, 2017.

NIGMS staff are located in the Natcher Building on the NIH campus.

In 2007, the FDA modified warfarin's label to indicate that genetic makeup may affect patient response to the drug. The widely used blood thinner is sold under the brand name Coumadin®. Scientists involved in the NIH Pharmacogenetics Research Network are investigating whether genetic information can be used to improve optimal dosage prediction for patients.

Structural biologists create crystals of proteins, shown here, as a first step in a process called X-ray crystallography, which can reveal detailed, three-dimensional protein structures.

Cell showing overproduction of the ARTS protein (red). ARTS triggers apoptosis, as shown by the activation of caspase-3 (green) a key tool in the cell's destruction. The nucleus is shown in blue. Image is featured in October 2015 Biomedical Beat blog post Cool Images: A Halloween-Inspired Cell Collection.

This image shows the hierarchical ontology of genes, cellular components and processes derived from large genomic datasets. From Dutkowski et al. A gene ontology inferred from molecular networks Nat Biotechnol. 2013 Jan;31(1):38-45. Related to 3437.

A crystal of Bence Jones protein created for X-ray crystallography, which can reveal detailed, three-dimensional protein structures.

These yeast cells were exposed to a glucose (sugar) shortage. This caused the cells to compartmentalize HMGCR (green)—an enzyme involved in making cholesterol—to a patch on the nuclear envelope next to the vacuole/lysosome (purple). This process enhanced HMGCR activity and helped the yeast adapt to the glucose shortage. Researchers hope that understanding how yeast regulate cholesterol could ultimately lead to new ways to treat high cholesterol in people. This image was captured using a fluorescence microscope.

Acetylsalicylate (bottom) is the aspirin of today. Adding a chemical tag called an acetyl group (shaded box, bottom) to a molecule derived from willow bark (salicylate, top) makes the molecule less acidic (and easier on the lining of the digestive tract), but still effective at relieving pain. See image 2530 for a labeled version of this illustration. Featured in Medicines By Design.

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

Model of an enzyme, PanC, that is involved in the last step of vitamin B5 biosynthesis in Mycobacterium tuberculosis. PanC is essential for the growth of M. tuberculosis, which causes most cases of tuberculosis, and is therefore a potential drug target.

This video condenses 6.5 minutes into less than a minute to show how the toxin in bee venom, called melittin, destroys an animal or bacterial cell. What looks like a red balloon is an artificial cell filled with red dye. Melittin molecules are colored green and float on the cell's surface like twigs on a pond. As melittin accumulates on the cell's membrane, the membrane expands to accommodate it. In the video, the membrane stretches into a column on the left. When melittin levels reach a critical threshold, countless pinhole leaks burst open in the membrane. The cell's vital fluids (red dye in the video) leak out through these pores. Within minutes, the cell collapses.

Crystal structure of oligoendopeptidase F, a protein slicing enzyme from Bacillus stearothermophilus, a bacterium that can cause food products to spoil. The crystal was formed using a microfluidic capillary, a device that enables scientists to independently control the parameters for protein crystal nucleation and growth. Featured as one of the July 2007 Protein Structure Initiative Structures of the Month.

A cell in metaphase during mitosis: The copied chromosomes align in the middle of the spindle. 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.

Crystal structure of the beta2-adrenergic receptor protein. This is the first known structure of a human G protein-coupled receptor, a large family of proteins that control critical bodily functions and the action of about half of today's pharmaceuticals. Featured as one of the November 2007 Protein Structure Initiative Structures of the Month.

Like a group of barnacles hanging onto a rock, these human cells hang onto a matrix coated glass slide. Actin stress fibers, stained magenta, and the protein vinculin, stained green, make this adhesion possible. The fibroblast nuclei are stained blue.

The parasitic worm that causes schistosomiasis hatches in water and grows up in a freshwater snail, as shown here. Once mature, the worm swims back into the water, where it can infect people through skin contact. Initially, an infected person might have a rash, itchy skin, or flu-like symptoms, but the real damage is done over time to internal organs.

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