Staining of NFIL3 (green) in nuclear bodies with DNA (blue) and microtubules (red) in A-431 cells. Many human genes follow a so called circadian clock and research has shown that some of those genes themselves follow the seasons (Dopico et al. 2015). When winter is coming, you sense it and your genes know it too. Expression of one of those genes, NFIL3, peaks during December until February and has its lowest expression during the summer months.

NFIL3 is a transcriptional regulator involved in regulation of immune processes. Like many other transcription regulators it localizes to nuclear bodies as seen on the Cell Atlas images and binds to specific DNA motifs...Read more

TPX2 was identified in 1997 as a 100 kDa nuclear protein. In cells TPX2, a is a microtubule nucleation factor that translocates from the nucleus - where it resides during interphase - to the mitotic spindle during mitosis.

The mitotic spindle forms when chromosomes are ready to segregate during cell division and not surprisingly this protein is also found in this specific compartment of the cell! TPX2 is required for the correct formation of the kinetochores that is crucial for the attachment of microtubules, enabling the sister chromatids to be pulled apart. Due to its function TPX2 expression is cell-cycle dependent...Read more

Mitochondria harbors an own genome that renders key proteins involved in production of energy through oxidation of various substrates. Majority of the disorders associated with mitochondrial function are caused by impaired expression of the proteins encoded in the mitochondrial genome. One of these proteins is the translational activator of cytochrome c oxidase 1 (TACO1).

Experimental results reveal that TACO1 is expressed in all tissues within the human body. The protein is detected mainly in the cytoplasm and more precise inside mitochondria. Explore expression and subcellular localization of TACO1 in the Cell Atlas...Read more

Within the Human Protein Atlas project, antibodies are used to study the localization of protein in human tissues and cells. To generate the antibodies recombinant expression clones are produced from human RNA pools by cDNA synthesis, cloning and plasmid purification. These clones produce what is called Protein Epitope Signature Tags (PrESTs), a selected part of the target protein that should be recognized by antibodies.

Johan Rockberg, Associate Professor in antibody technology and directed evolution at KTH - Royal Institute of Technology in Stockholm, Sweden is the group leader for the epitope mapping and therapeutic antibodies group within the Human Protein Atlas...Read more

Mitochondria are responsible for the energy production in our cells. The most interesting thing about mitochondria is that they have their own DNA which means some proteins in the mitochondria come from nuclear DNA and some from mitochondrial DNA. In a previous image of the week we highlighted TOMM5, a protein responsible for transport of nuclear encoded mitochondrial proteins into the mitochondria.

In this week's image of the week we take a look at citrate synthase (CS), a nuclear encoded mitochondrial protein that is a key enzyme for the citric acid cycle of the cell (TCA cycle), also known as the Krebs cycle...Read more