Biology of SARS-CoV-2: Infection | HHMI BioInteractive Video
Aug 28, 2020 13:41 · 330 words · 2 minute read
[crickets] [footsteps] [cymbal plays] [chime] [music plays] This is the virus SARS-CoV-2. Its name stands for severe acute respiratory syndrome coronavirus 2. You may have heard it called just the “coronavirus” or COVID-19. Coronaviruses are actually a family of viruses that includes SARS-CoV-2. And COVID-19 is the name of the disease caused by it.
00:39 - Coronaviruses infect humans and other animals. In humans, they cause the common cold and, in some cases, more serious respiratory diseases. All coronaviruses, including SARS-CoV-2, have a genome made of a single strand of RNA, which is surrounded by a membrane made of lipids and proteins. This membrane is called an envelope. Coronaviruses are named after what looks like a crown of protein spikes that stick out of their envelope. Coronaviruses enter the body mainly through the mouth or nose.
01:18 - The virus then has to get inside a human cell. The protein spikes on the virus’s envelope attach to specific proteins on the surface of a cell. This causes the virus’s membrane to fuse with the cell’s membrane, releasing the virus’s RNA genome into the cell. The cell’s ribosomes translate the virus’s RNA into proteins, including viral RNA polymerase. The RNA polymerase transcribes the virus’s RNA, making more RNA copies that are translated into proteins.
01:50 - It also makes more copies of the virus’s whole genome. The new viral genome and proteins combine to make a new virus that is packaged into an envelope formed from the cell’s membranes. Newly formed viruses travel to the cell’s surface and are released outside the cell. These viruses can infect other cells, or leave the body in mucus and saliva droplets. This can all happen even if a person doesn’t feel sick or show symptoms of disease.
02:21 - A fever or coughing are usually signs that the immune system is fighting the infection. The production of new viruses continues, until the body’s immune system is able to eliminate the infection. [music plays] .