A Cartoon Analogy to Explain Protein Synthesis in Eukaryotes:-

 CENTRAL DOGMA IN EUKARYOTES-CARTOON ANALOGY

A CARTOON ANALOGY

The transcription and the translation, the two major phases of the Central Dogma of a eukaryotic cell can be made easy and simplified to understand with the above shown analogous cartoon figure.

In the eukaryotes, unlike in the prokaryotes, the transcription phase occurs within the nucleus.

It is analogous to taking a copy of a particular cooking recipe from the original cookery guide book.

The original cookbook is the entire DNA chain embossed in the chromosome strand.

The particular page that contains the recipe to be transcribed is a gene portion of the DNA strand.

The copy making machine is the enzyme, DNA dependent  RNA Polymerase (RNAP).

The transcribed raw copy before the proofreading is the immature mRNA.

The proof-reader is the snRNA

After the proofreading (splicing) the matured mRNA swim out from the nucleus into the cytosol for translation.

The translation phase occurs in the cytosol.

In translation, there are many types of utensils that fit to bring suitable raw material to the cooker.

The utensils are the tRNAs

The raw materials are the amino acids

The cooker is the ribosome

The finished product is the protein molecule.

 

NINE ESSENTIAL AMINOACIDS

  ESSENTIAL AMINO ACIDS

  We have studied that protein synthesis is necessary for our body to maintain good health and energy. All our body cells are synthesizing various necessary proteins on a daily routine basis except a few which synthesize some proteins as per the body's need.

Amino acids are the basic molecules to build up proteins. There are twenty amino acids that are essential to synthesize various proteins.

Out of the 20 amino acids, our body can make only 11 amino acids. The other 9 amino acids must be supplied to our body either through food or through medicines only.

The 9 amino acids with their respective mRNA codons are the essential amino acids that the body cannot synthesize and to be supplied to the body through diet or medicines.

Generally, proteinous foods especially, meats, milk, eggs, soybeans, nuts, seeds, dry fruits are all rich in essential amino acids.

All amino acids are used to build proteins

There are additional two amino acids namely selenocysteine and pyrrolysine that do not have codons but they can be incorporated into the polypeptide chain by tRNAs holding complementary codons to the stop codon in the mRNA. Proteins containing selenocysteine are enzymes like glutathione peroxidases, tetraiodothyronine 5'-deiodinases, thioredoxin reductases, formate dehydrogenases, etc.  Proteins containing Pyrrolysine are rare can be present in archaea. 

The 9 essential amino acids are,

1.Lysine                                  

2.Leucine              

3.Isoleucine

4.Methionine

5.Phenylalanine

6.Threonine

7.Tryptophane

8.Histidine

9.Valine

Lysine containing foods 

Lysine is used especially to synthesize carnitine a group of essential substances like L-carnitine which give energy to the body. L-carnitine improves insulin sensitivity to the tissue cells.

The followings are the lysine-rich foods:-

1. Mutton, Beef, Chicken

2.Permesan Cheese (A hard full-fat Italian cheese)

3.Cod Fish and Sardines

4.Eggs

5.Soybeans, especially the curd made out of soy milk (Tofu)

6.Sprulina (A blue-green algae, a cyanobacterium belongs to Arthrospira Platensis).

7.Fenugreek Seed (வெந்தயம்)

Leucine-Rich Foods

Leucine improves protein synthesis in our body which compensates and prevents body muscle wasting.

It has been shown that leucine improves insulin production and secretions.

The followings are the Leucine-rich foods

1.Concentrated Whey Protein

2.Soy Protein concentrated

3.Pea Protein

4.Soy bean

5.Hemp seeds hulled

6.Beef

7.Salmon Fish

8.Wheat Germ

9.Almonds

10.Broiled or Fried Chicken thigh.

Isoleucine Rich Foods

Isoleucine helps our body, by regulating protein and fat metabolism, increasing protein synthesis.decreasing muscle waste.

The followings are the isoleucine rich foods:-

1.Beef

2.Veal

3.Lamb

4.Chicken

5.Wheat germ

6.Legumes

7.Seeds

8.Bakery Yeast.

Methionine

Methionine is used to prevent liver damage by paracetamol overdose. 

The followings are the methionine rich foods.

1.Ground Turkey

2.Beef

3.Tuna

4.Soya curd (Tofu)

5.Milk

6.Brazil nuts

7.Large White Beans

Phenylalanine

Phenylalanine, in addition to its effect on protein synthesis it is used to synthesize molecules that exchange signals between various body parts. Also, it is used in many skin disorders, depressions, and pain.

The followings are phenylalanine rich foods

1.Milk

2.Eggs

3.Cheese

4.Nuts

5.Chicken

6.Beans

7.Fish

Threonine

Threonine other than its role in protein synthesis it is used in nerve disorders like spinal spasticity, multiple sclerosis, familial spastic paraparesis, and amyotrophic lateral sclerosis.

The followings are the threonine rich foods:-

1.Cottage cheese

2.Chicken

3.Fish

4.Lentils

5.Lean beef

6.Soy

7.Nuts

Tryptophane

In addition to its role in protein synthesis, tryptophane also used to synthesis brain signaling molecules. The brain converts tryptophan to 5-hydroxytryptophan (serotonin) that improves our mood and sleep. Tryptophan-rich foods:-

1.Chocolate

2.Oats

3.Dried Dates

4.Milk, Yogurt, and Cottage cheese

5.Mutton, Beef

6.Eggs, and Poultry

7.Fish

8.Sesame, Chickpeas

9.Almonds and Peanuts

10.Sunlower seeds, Pumpkin seeds, buckwheat 

and Spirulina.

Histidine

In addition to its role in protein-synthesis, histidine is used in Rheumatoid Arthritis, Allergy, Ulcers, Anemia, and Kidney failure.

Histidine rich foods,

1.Poultry

2.Whole wheat grains

Valine

In addition to its role in the synthesis of protein,  valine improves muscle growth, muscle regeneration, and energy production. The followings are the valine rich foods.

1.Soy

2.Cheese

3.Peanuts

4.Mushroom

5.Beef, Chicken, Mutton.