Protein synthesis | Transcription, Translation and Translocation

Notes On Protein Synthesis

Protein synthesis is a fundamental biological process that is crucial for all living organisms. In class 10 biology, understanding this concept lays the groundwork for more advanced studies in genetics and molecular biology. This blog aims to provide a detailed yet straightforward explanation of protein synthesis, making it easier for students to grasp this essential topic.

 

What is Protein Synthesis?

Protein synthesis is the process by which cells build proteins, which are vital for various cellular functions, including structure, function, and regulation of tissues and organs.  

What is Central Dogma?

Information about protein synthesis is stored in the DNA and synthesis of appropriate proteins as per requirement is necessary for body. These proteins are synthesized by DNA through RNA. This is called as 'Central Dogma'.

There are main three important steps involved in the process of protein synthesis: Transcription, Translation and Translocation

Transcription (Synthesis of RNA) :

• Only one of the two strands of DNA is used in this process. The sequence of nucleotides in mRNA being produced is always complementary to the DNA strand used for synthesis. This process of RNA synthesis is called as ‘transcription’.

• (Transcription takes place in nucleus).

• [ In DNA Cytosine C, Guanine G, Adenine A and Thymine T are present.

• In RNA Cytosine C, Guanine G, Adenine A and Uracil U are present i.e. In RNA Thymine T is replaced by Uracil U ]

• mRNA is produced as per the sequence of nucleotides on DNA.

• Translation :

• The mRNA formed in nucleus comes in cytoplasm. It brings the coded message from DNA. 

• The code for each amino acid consists of three nucleotides. It is called as 'Triplet codon'.  

• As per the message on mRNA, amino acids are supplied by the tRNA. For this purpose, tRNA has 'anticodon' having complementary sequence to the codon on mRNA. This is called Translation. 

• Translocation :

• The ribosome keeps on moving from one end of mRNA to other end by the distance of one triplet codon. This is called Translocation. such many chains come together to form complex proteins.

• These proteins control various functions in the body of living organisms and their appearance too.

• Gene mutation : Sometimes any nucleotide of the gene changes its position, that causes a minor change which is nothing but the mutation.

• Mutation may cause the genetic disorders like sickle cell anemia. 

• Terms to remember :

• Central Dogma: The process of synthesis of  proteins from DNA through RNA is called Central Dogma.

• Transcription: The process of RNA synthesis from DNA is called as Transcription.

• Triplet codon: The code for each amino acid consists of three nucleotides. It is called as Triplet codon.

• Translation: As per the message on mRNA, amino acids are supplied by the tRNA. For this purpose, tRNA has 'anticodon' having complementary sequence to the codon on mRNA. This is called Translation.

• Translocation: The ribosome keeps on moving from one end of mRNA to other end by the distance of one triplet codon. This is called Translocation.

• Mutation: Any sudden change that occurs in the nucleotide sequence of a gene, causing a minor or considerable change in the characters of an individual is called mutation.