One gene, zero to protein — live
A stylized eukaryotic cell running the central dogma in real time. Drag to pan, scroll or pinch to zoom, and click any part — from the promoter to the finished protein — for what it is, what it does, and a fact worth remembering.
DRAG TO PAN · SCROLL OR PINCH TO ZOOM · CLICK ANY PART — CLICK AGAIN TO CLEAR
Four ways to explore
No manual required — but these make it richer.
Press play
Run the whole process — transcription, export, translation, folding — on a loop. Pause anywhere to poke around.
Click anything
Every element of the model is a card waiting to open: the gene, the polymerase, codons, tRNAs, the growing chain — fourteen in total.
Get closer
Drag to pan, scroll or pinch to zoom. Go in far enough and you can read the individual codons printed on the mRNA.
Take the tour
The arrows under the model walk you through all fourteen parts in the exact order the process really happens. Arrow keys work too.
The ideas doing the work
Four concepts carry everything you see in the model.
The central dogma
Information flows one way: stored in DNA, copied into RNA, spent as protein. This tool walks that road end to end, inside one cell.
Transcription = copying
The gene stays in the nucleus — like reading a library book without taking it off the shelf. Only the copy travels.
Translation = building
Every three mRNA letters name one amino acid. The ribosome chains them into the exact protein the gene spelled out.
Expression = control
Nearly every cell in your body has the same genes. What makes a muscle cell a muscle cell is which genes are switched on — that is what "gene expression" really measures.
Frequently asked questions
Everything people usually ask about the model, the biology, and the tool itself. The same questions are indexed for search engines, so this page can answer them directly.
What is gene expression, in one sentence?+
Gene expression is the two-step process of turning information stored in a gene into a working product: the gene is copied from DNA into mRNA (transcription), and that mRNA is read by ribosomes to build a protein (translation).
What's the difference between transcription and translation?+
Transcription happens in the nucleus: RNA polymerase reads the DNA gene and builds a matching mRNA copy. Translation happens in the cytoplasm: ribosomes read that mRNA and link amino acids into a protein. Copy first, build second.
What do the three-letter codes on the mRNA mean?+
They're codons — groups of three mRNA letters that each name one amino acid. AUG is the start codon; UAA, UAG and UGA are stop codons. 64 codons cover 20 amino acids, so several codons can spell the same one.
What order should I follow the diagram in?+
Start at the DNA and its highlighted gene, watch RNA polymerase copy it, follow the mRNA out through the nuclear pore, then meet the ribosome reading codons and the tRNAs delivering amino acids. The tour arrows walk the 14 parts in exactly this order.
Is this a plant, animal, or bacterial cell?+
It's a stylized eukaryotic cell — the kind with a nucleus — so transcription and translation happen in separate places. In bacteria there's no nucleus, so ribosomes start translating mRNA while it's still being transcribed.
Does the animation show real speeds and sizes?+
No — it's a readable model, not a clock. Real RNA polymerase adds dozens of nucleotides per second and ribosomes build 2–20 amino acids per second; a real mRNA is thousands of letters long, and the molecules are nowhere near these proportions.
Does the tool upload or save anything?+
No. The model runs entirely in your browser — nothing you click, zoom, or play is sent to a server, logged, or stored.
Is it free, and does it work on phones and tablets?+
Yes — completely free with no account or sign-up. Tap to select, drag to pan, and pinch to zoom, so it works the same on touch screens as with a mouse.