Difference Between Template and Coding Strand

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The difference between template and coding strand is mainly due to the following properties like directional polarity and their function. Both are the two different strands of the double-stranded DNA, where template strand works as a template or base to transcribe mRNA, and the other determines the correct base sequence of the mRNA.

Directional Polarity: The template strand moves from the 3’end to the 5’ end whereas the coding strand moves opposite to the direction of the template strand, i.e. from 5’end to 3’ end.

Base Sequence: The base sequence of the template strand is complementary to both the coding strand and the mRNA strand. Whereas the base sequence of the coding strand is as similar to the new mRNA strand except for one change, where uracil present in place of thymine.

Content: Template Vs Coding Strand

  1. Comparison Chart
  2. DefinitionofTemplateStrand
  3. Definition of Coding Strand
  4. Key Differences Between Template and Coding Strand
  5. Conclusion

Comparison Chart

PropertiesTemplate strandCoding strand
Alternative namesAntisense, Minus or Non-coding strandSense, Plus or Non-template strand
FunctionActs as the template for the RNA synthesisDetermines the sequences of the RNA strand
Directional polarityMoves in a 3’-5’ directionMoves in a 5’-3’ direction
Reading by RNA polymeraseRNA polymerase reads the template strand from 3’ to 5’ endRNA polymerase do not read the coding strand
Nucleotide base sequenceIts base sequence is complementary to the both coding strand and the mRNAIts base sequence is same as the newly formed mRNA, but in place of thymine uracil is present
Genetic codingTemplate strand consists of “Anticodons”Coding strand consists of “Codons”
Formation of Hydrogen bondHydrogen bond forms temporally between the template strand and the newly synthesizing mRNA at the time of transcriptionNo such bond forms

Definition of Template Strand

Template strand can define as the strand of a DNA whose base sequence is used to synthesize mRNA by the complementary base sequencing. Template strand, also known as “Antisense strand” which runs in 3’- 5’ direction opposite to the coding strand. It contains complementary nucleotide sequences to the transcribed mRNA. After transcription, the mRNA before converted into mature mRNA undergoes certain modifications refers as a post-transcriptional modification.

The template strand also contains “Anticodons” which carries triplet codes or triplet nucleotide sequences which are complementary to the Anticodon sequence of the t-RNA. The anticoding helps in the attachment of the specific amino acid to the t-RNA and further processed by the r-RNA to form protein or a peptide chain.

A template strand is used by the RNA polymerase to make RNA transcript by recognizing the promoter genes or sequences. Hence, RNA polymerase is the one who decides when to initiate the process of transcription and when to terminate the process of translation.

Example
Suppose, the template strand carries 5’- A T C G C G T A – 3’ gene sequence. The RNAP will first bind to the promoter region of the DNA sequence and promotes the process of transcription. By the attachment of RNAP with the promoter site, the template strand will transcribe to form the primary mRNA transcript.

As we have discussed the mRNA will form complementary base sequences to that of the template strand. Therefore mRNA will carry  3’- U A G C G C A U – 5’ base sequence.

example of coding in template and rna strand

Definition of Coding Strand

Coding strand can define as one of the DNA strand, which has a quadrate base sequence with the primary mRNA or the transcribed mRNA. The base sequence of mRNA, which is similar to the coding strand, will contain the same nucleotide bases except for thymine. In place of thymine, uracil is a nucleotide base which presents in the RNA.

It also refers as “Sense strand” which runs in a 5’- 3’ direction opposite to the template strand. As the RNAP uses the template strand to transcribe the mRNA, the other strand will be the sense strand which will form a complementary strand to that of the template. It contains triplet codons that code for the specific amino acid to build a protein as a result of RNA translation.

Example
Suppose, the template strand carries 5’- A T C G C G T A – 3’ gene sequence. The coding strand will produce complementary pairs will the template strand according to the Watson and Crick model.

Therefore, the base sequence of the sense strand will be 3’- T A G C G C A T – 5’. The RNAP will bind to the promoter region of the DNA sequence and promotes the process of transcription.

By the attachment of RNAP with the promoter site, the template strand will transcribe to form the primary transcript with a base sequence 3’- U A G C G C A U – 5’.

example of coding in template,coding and rna strand

Key Differences Between Template and Coding Strand

  1. Minus, antisense and non-coding strand are the alternative names for the template strand whereas plus, sense and non-template strand are the alternative names for the coding strand.
  2. Template strand functions as the template for RNA synthesis and transcribes mRNA. The coding strand functions to determine the correct nucleotide base sequence of the RNA strand.
  3. The direction of the template strand is 3’ to 5’ direction whereas the coding strand shows opposite directional polarity, i.e. 5’ to 3’ direction.
  4. The RNA polymerase reads the non-coding or template strand from the 3’-5’ direction and polymerize the RNA transcript by adding complementary nucleotides to that of the template strand.
  5. The nucleotide base sequence of the template strand (3’-5’) is complementary to the base sequence of both the sense strand and the mRNA transcript (5’-3’).
  6. The antisense strand consists of anticodons of the t-RNA, whereas the sense strand includes codons which code the specific amino acid to form a peptide chain.
  7. Hydrogen bond forms temporarily between the template strand and the newly synthesized mRNA at the time of transcription whereas coding strand does not establish such type of bond with the mRNA.

Conclusion

Both the sense and antisense strand of DNA coordinates to transcribe RNA and further translates into proteins. Sometimes, the two strands of the DNA refers as “Watson” and “Crick” strand named after the two scientists Watson and Crick who gave the model of double-stranded DNA.

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