Key differences in eukaryotic and prokaryotic translation process and mechanisms
The process used to transfer the genetic information stored in the DNA into units of transportable complementary RNA replicas, is called Eukaryotic Transcription.
In prokaryotes transcription occurs in the cytoplasm of the cell as it lacks the membrane-bound nuclei and other organelles.
Difference Between Prokaryotic And Eukaryotic Translation
In the process of translation, the nucleotide triplets, also known as the codons, present on the mRNA will be translated into amino acid sequence.
Protein synthesis involves the process of Eukaryotic and Prokaryotic Translations.
The major difference between eukaryotic and prokaryotic translation that lies is that the eukaryotic translation and transcription is a process that is asynchronous whereas prokaryotic translation and transcription is a synchronized process. The Difference between Prokaryotic And Eukaryotic Translation are as follows -
Cell Size
Eukaryotic cells are larger (10 – 100um) than the prokaryotic cells (1 – 10um).
Cell Arrangement
The arrangement of the cells are also different. Eukaryotes are often multicellular whereas prokaryotes are unicellular.
True Membrane-Bound Nucleus
Eukaryotic cells double membrane surrounded by true nucleus. It performs the functions of the large cell in a smaller enclosure to ensure that there is close proximity to materials and increased efficiency for cellular communication and functions that are generally DNA-related.
DNA Structure
Eukaryotic DNA is linear and complex along with the packaging proteins that are known as the "histones," named before organization into a number of chromosomes. Prokaryotic DNA is circular. It is neither linked with histones nor organized into chromosomes.
For a clear understanding of the differences between Prokaryotic and Eukaryotic Translations, have a look at the table below -
Differences Between Prokaryotic and Eukaryotic Translations
Prokaryotic Cells
Prokaryotes are one of the most ancient groups of living organisms which derives the meaning as being ‘Before Nuclei’ on earth, with fossil records dating back to almost 3.5 billion years ago.
These prokaryotes were found in the earth’s ancient environment, some using up chemical energy and others using the sun’s energy. These extremophiles survived for millions of years, evolving and adapting. Scientists made a conclusion that these organisms gave rise to the eukaryotes.
Eukaryotic Cells
Eukaryotes are more complex and much larger than the prokaryotes. Almost all the major kingdoms are included in this except for kingdom monera. Structure wise, eukaryotes possess a cell wall, which supports and protects the plasma membrane. The cell is surrounded by the plasma membrane and it controls the entry and exit of certain substances.
Similarities Between Eukaryotic and Prokaryotic Cells
Along with some differences, there are also some similarities between the Eukaryotic and Prokaryotic Cells. The similarities are the following -
Cell Membrane
Both eukaryotic and prokaryotic cells consist of a lipid bilayer, which is an arrangement of phospholipids and proteins that is a selective barrier between the internal and external environment of the cell.
Genetic Material
Both the Eukaryotic and prokaryotic cells use deoxyribonucleic acid (DNA) as the basis for their genetic information. This genetic material is needed to regulate and perform the cell function through the creation of RNA by transcription, followed by the generation of proteins through translation.
Ribosomes
Ribosomes help in theRNA translation and also the creation of protein, which is essential to the smooth functioning of both eukaryotic and prokaryotic cells.
Cytoplasm
The cytoplasm is the place in which the biochemical reactions of the cell take place, of which the primary component is cytosol. In eukaryotic cells, the cytoplasm consists of everything between the plasma membrane and the nuclear envelope, including the organelles; the material within the nucleus is termed the nucleoplasm.
FAQs on Eukaryotic and Prokaryotic Translation Explained
1. What is the difference between translation in prokaryotes and eukaryotes?
The main difference between prokaryotic and eukaryotic translation is that prokaryotes translate mRNA in the cytoplasm simultaneously with transcription, while eukaryotes separate transcription (nucleus) and translation (cytoplasm).
- Prokaryotes: Translation occurs in the cytoplasm and can begin before transcription is complete.
- Eukaryotes: mRNA is processed (capping, polyadenylation, splicing) in the nucleus before being exported for translation.
- Ribosome size differs: 70S in prokaryotes and 80S in eukaryotes.
2. What is translation in eukaryotic cells?
Translation in eukaryotic cells is the process by which ribosomes synthesize proteins using the information encoded in mRNA.
- Occurs in the cytoplasm or on the rough endoplasmic reticulum.
- Requires processed mRNA with a 5′ cap and poly-A tail.
- Involves three stages: initiation, elongation, and termination.
3. What is translation in prokaryotic cells?
Translation in prokaryotic cells is the synthesis of proteins directly from mRNA in the cytoplasm, often occurring simultaneously with transcription.
- Occurs on 70S ribosomes (50S + 30S subunits).
- Does not require mRNA processing like splicing.
- Initiation begins at a Shine–Dalgarno sequence.
4. How does initiation of translation differ in prokaryotes and eukaryotes?
Initiation differs because prokaryotes use a Shine–Dalgarno sequence for ribosome binding, while eukaryotes use a 5′ cap-dependent scanning mechanism.
- Prokaryotes: The small ribosomal subunit binds directly to the Shine–Dalgarno sequence near the start codon.
- Eukaryotes: The small subunit binds to the 5′ cap and scans to find the AUG start codon within a Kozak sequence.
5. Why can transcription and translation occur simultaneously in prokaryotes but not in eukaryotes?
Transcription and translation occur simultaneously in prokaryotes because they lack a nuclear membrane, while eukaryotes separate these processes into nucleus and cytoplasm.
- Prokaryotes: No nucleus, so ribosomes access mRNA as it is being transcribed.
- Eukaryotes: Transcription occurs in the nucleus and translation in the cytoplasm.
- Eukaryotic mRNA must undergo processing before export.
6. What are the ribosome sizes in prokaryotic and eukaryotic translation?
Prokaryotic ribosomes are 70S, while eukaryotic ribosomes are 80S.
- 70S ribosome: Composed of 50S (large) and 30S (small) subunits.
- 80S ribosome: Composed of 60S (large) and 40S (small) subunits.
7. What is the role of mRNA processing in eukaryotic translation?
mRNA processing in eukaryotes prepares the transcript for translation by adding a 5′ cap, poly-A tail, and removing introns via splicing.
- The 5′ cap helps ribosome recognition and stability.
- The poly-A tail increases mRNA stability and export.
- Splicing removes introns and joins exons.
8. What is the function of the Shine–Dalgarno sequence in prokaryotic translation?
The Shine–Dalgarno sequence is a ribosome-binding site that aligns the mRNA with the 30S ribosomal subunit to initiate translation in prokaryotes.
- Located upstream of the start codon.
- Base-pairs with rRNA in the small ribosomal subunit.
- Ensures correct positioning of the AUG start codon.
9. Are start codons the same in prokaryotic and eukaryotic translation?
The primary start codon in both prokaryotes and eukaryotes is AUG, but the initiating amino acid differs.
- Prokaryotes: AUG codes for N-formylmethionine (fMet).
- Eukaryotes: AUG codes for methionine (Met).
10. What are the main similarities between eukaryotic and prokaryotic translation?
Both eukaryotic and prokaryotic translation use ribosomes to decode mRNA into proteins through initiation, elongation, and termination.
- Both follow the genetic code.
- Both require tRNA, ribosomes, and translation factors.
- Both synthesize polypeptides in the 5′ to 3′ direction of mRNA reading.
