Proteins: A Look at Their Composition and Synthesis

Proteins: A Look at Their Composition and Synthesis

Nonconformist Guide to the Marvels of Proteins

Proteins, baby! They're the showstoppers of every living organism. From catalyzing reactions to defending against infections, these molecules are the lifeblood of every cell. And the best part? They're all made in the same two-step process - protein synthesis.

First, DNA transcribes into RNA, and then RNA gets translated into protein. Simple, right? But don't be fooled, there's a whole lot more going on beneath the surface of that simple process.

Protein: The Wonder Molecule

Proteins are made of a kickass chain of amino acids. These building blocks come together to form complex, origami-like shapes that control what the protein does. Each protein's unique shape and the amino acids it contains dictate its function.

Key Players in the Protein Circus

Enzymes are a subcategory of proteins that have multiple applications in medical and industrial biotechnology. Check out our video clip on Improving enzymes to learn more.

Insulin, another essential protein, is crucial for regulating blood sugar levels. Type 1 diabetics do not produce insulin naturally, so learning about it (via our video clip on Type 1 diabetes) is key.

Protein in Action

Mussels stick to rocks and piles with their strong proteins, and an interactive on How mussels are farmed in New Zealand will show you how it's done. Antibodies, proteins that help fight infection, and casein, the protein in milk that helps make cheese, are other must-knows. And transcription factors, specialized proteins that control the production of other proteins, are worth checking out too.

The Printing Press of Genes

Every organism makes proteins in the same way - through a process called gene expression. It's split into two stages: transcription and translation.

During transcription, the ribosome reads the DNA sequence between the start and end of a gene and produces an mRNA (molecular messenger RNA) message that reflects the sequence of the gene itself.

In the translation phase, the ribosome gets the mRNA message and starts building a protein chain based on the mRNA instructions. The ribosome "reads" the mRNA as a series of three-letter chunks, known as codons, which tell the protein-making machinery which amino acid to add next.

Unleashing the Genetic Code

Here's the mind-blowing part: the genetic code is essentially the same throughout nature. It works irrespective of whether the protein is being made in bacterial cells or human cells. Each codon has the same 'meaning' in any given cell, and every cell follows the same rules to make a protein.

The Power of a Promoter

In your typical cell, not all proteins are produced at the same time or in equal quantities. Some proteins that perform essential roles are produced constantly, while others are only expressed when needed. And of course, cells need varying amounts of proteins, like enzymes involved in continuous processes, versus smaller amounts of proteins like hormones. But how does a cell decide which genes to express and how much to make?

Enter transcription factors, proteins that bind to the regulatory regions of genes, known as promoters, and either turn gene expression on or off. Some transcription factors allow certain genes to be expressed at higher levels, while others limit gene expression.

Promoters and Apple Flesh Color

Researchers at Plant & Food Research have found that transcription factors play a key role in determining whether apples have white or red flesh. By studying the promoters of genes that produce red pigment in apples, they discovered that a transcription factor (MYB10) binds to these promoters, causing the genes to be expressed at higher levels, leading to more red pigment production.

The Masterplan

Curious about genetics and the wonders of proteins? Here are some resources that dive deeper into gene expression, protein synthesis, and everything in between:

• DNA, chromosomes, and gene expression
• The role of proteins in the body
• RNA interference

For a fun, interactive exploration of genetics concepts, check out the resources from the Genetic Science Learning Center at The University of Utah.

1. Delving into health and wellness, understanding the role of proteins in regulating medical conditions such as Type 1 diabetes is crucial, especially since Type 1 diabetics lack natural insulin production.
2. In the realm of fitness and exercise, proteins like transcription factors also play a significant role in controlling the production of other proteins. For instance, researchers at Plant & Food Research discovered that transcription factors influence the color of apple flesh.

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