A brief text version after the video

In our cells, all the original recipes for making all the proteins and functional RNAs we will ever need are written in the form of DNA as genes. Those genes are present in the form of really long, really coiled-up pieces of DNA called chromosomes, which you can think of like cookbooks. And the full complement of cookbooks, referred to as the genome, is stored in a membrane-bound compartment of the cell called the nucleus. This protects them from damage, which is important because we don’t want to mess up those original copies! But, it also separates them from the chefs (protein/RNA complexes that use the instructions to make the corresponding proteins), which are located in the cytoplasm (general cellular interior). Therefore, in order to make a protein, cells first make a messenger RNA (mRNA) copy of the gene in a process called transcription.  

The pre-mRNA that’s first made gets processed a little to remove regulatory regions called introns (in a process called mRNA splicing) and it gets a cap and a tail to protect its ends, and then that mature mRNA gets exported into the cytoplasm to meet the chefs. In addition to protecting the original recipes, this set-up allows for signal amplification because you can make lots of copies of the original and each copy can be used lots of time. It also allows multiple different versions of a protein to be made by processing the recipe copies differently during maturation (e.g. through alternative splicing). https://bit.ly/altsplicing  

Protein-making occurs in a process called translation, where ribosomal “chefs” link together amino acids (protein letters) based on the mRNA instructions. 3 consecutive RNA letters spells one amino acid (protein letter). These 3-letter words are called codons and when the ribosomes encounters a codon, a transfer RNA (tRNA) with the complementary 3-letter “anticodon” brings the corresponding amino acid.  The ribosome links it to the growing polypeptide chain that folds up into a functional 3D protein. 

So, to summarize  – we have original protein recipes written in DNA as genes -> mRNA copies get made in a process called transcription in the nucleus -> those mRNA copies get exported into the cytoplasm to be used by ribosomes to make proteins.  

more on topics mentioned (& others) #365DaysOfScience All (with topics listed) 👉 http://bit.ly/2OllAB0

link to slides: http://bit.ly/cakebakingslides

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