Describe two ways in which gene regulation differs and two...

Describe two ways in which gene regulation differs and two ways in which it is similar in prokaryotes and eukaryotes. a. Prokaryotes show co-transcriptional translation whereas eukaryotes perform transcription prior to translation; in both cell types, regulation occurs through the binding of transcription factors, activators, and repressors. b. Prokaryotes perform transcription prior to translation whereas eukaryotes show cotranscriptional translation (the processes occur in the same organelle). c. Prokaryotes show co-transcriptional translation that is regulated prior to translation whereas eukaryotes perform transcription prior to translation that is regulated only at the level of transcription. In both domains, transcription factors, activators, and repressors provide regulation. d. Prokaryotes show co-transcriptional translation that occurs in the nucleus whereas eukaryotes show transcription prior to translation. In both cell types, regulation occurs using transcription factors, activators, and repressors.

Describe two ways in which gene regulation differs and two ways in which it is similar in prokaryotes and eukaryotes.
a. Prokaryotes show co-transcriptional translation whereas eukaryotes perform transcription prior
to translation; in both cell types, regulation occurs through the binding of transcription factors, activators, and repressors.
b. Prokaryotes perform transcription prior to translation whereas eukaryotes show cotranscriptional translation (the processes occur in the same organelle).
c. Prokaryotes show co-transcriptional translation that is regulated prior to translation whereas eukaryotes perform transcription prior to translation that is regulated only at the level of transcription. In both domains, transcription factors, activators, and repressors provide regulation.
d. Prokaryotes show co-transcriptional translation that occurs in the nucleus whereas eukaryotes
show transcription prior to translation. In both cell types, regulation occurs using transcription factors, activators, and repressors.

Key Concepts

Regulatory Proteins (Transcription Factors, Activators, and Repressors)

Both prokaryotes and eukaryotes utilize regulatory proteins to control gene expression. These proteins, including transcription factors, activators, and repressors, bind specific DNA sequences to either promote or inhibit the transcription of genes. This common regulatory strategy highlights the conserved importance of modulating gene expression in response to internal and external signals across different cellular life forms.

Transcription and Translation in Eukaryotes

In eukaryotes, transcription and translation are spatially separated processes occurring in the nucleus and cytoplasm respectively. This separation adds additional layers of regulation including mRNA processing events such as splicing, capping, and polyadenylation, which collectively allow for more complex regulation of gene expression necessary for multicellular organisms.

Cotranscriptional Translation versus Sequential Processing

A key difference between prokaryotic and eukaryotic gene expression is that prokaryotes can perform translation while transcription is still in progress, known as cotranscriptional translation. In contrast, eukaryotes complete transcription and subsequent RNA processing in the nucleus before exporting mRNA to the cytoplasm for translation, reflecting a more compartmentalized and regulated process.

Gene Regulation

Gene regulation refers to the control of the timing, location, and amount of gene expression and is crucial for cellular function, development, and adaptation. It involves various mechanisms that control the transcription and translation processes to ensure that genes are expressed appropriately for the cell's needs and environmental conditions.

Transcription and Translation in Prokaryotes

In prokaryotes, transcription (the process of creating RNA from a DNA template) and translation (the synthesis of proteins from mRNA) occur almost simultaneously because both processes take place in the cytoplasm. This coupling allows for rapid responses to environmental changes, and the control mechanisms often involve the regulation of transcription initiation as well as mechanisms that affect mRNA stability.

Transcript

00:01 We are being asked to compare and contrast prokaryat and eukaryote gene expression.

00:08 So real quickly, let's look at prokaryotes.

00:10 Prokaryotes have a circular genome.

00:13 And throughout that circular genome, you have different genes dispersed throughout.

00:21 And over here, i've drawn one exaggerated version of that.

00:25 In the green is the gene that encodes for a protein.

00:27 And in the red you have the promoter region or the operator region.

00:34 And to that promoter or operator, transcription factors or repressors or activators can bind, which can then lead to the transcription of the gene.

00:44 So suppose that we have all of the correct activators and transcriptional factors in place and all of the repressors for this gene have been removed.

00:54 Then rna polymerase can bind to the gene.

00:57 It can start making rna.

01:00 And while that rna is still being synthesized, while it's still being transcribed, a ribosome can bind to that rna and start making protein right away.

01:11 And that's what referred to as co -transcriptional translation.

01:18 So translation is happening at the same time as transcription because there's no division of space of nucleus and cytoplasm in prokary.

01:27 And the only level of regulation happens at the level of the regulatory region on the gene, which is promoter or operator region by the binding of transcription factors or repressors.

01:40 Similar in eukaryotes, you have the gene that is being transcribed and you have a promoter slash regulatory region to that promoter or to that operator, different proteins can bind and those proteins can be reprimand.

01:57 Repressers or activators or transcription factors that modulate the transcription of the protein.

02:05 Once the gene is transcribed, you have pre -mrna, that pre -mrna gets processed into mature rna, messenger rna through the addition of five prime caps and poly a -tail additions through splicing and through the binding of rna binding proteins.

02:22 And then once that rna is by it once that mature mrna is produced, it can be translated into protein and then the protein can be further modified through the addition of chemical groups like phosphate groups.

02:36 And just so that it sort of sticks a little bit more since i haven't used blue.

02:43 Let me use blue here.

02:45 You have in this step here, you have transcription.

02:50 Transcription so from so what i've drawn here that is a chromosome like an x chromosome and you pick one gene from the chromosome you try you transcribe it into pre -m rna you process the pre -mrna into mrna and then the mri makes it out into the cytoplasm i'm sorry for the double arrows i'm not really sure what i was thinking at that moment but i hope you can follow so the mature and a morena after processing makes it out into the nucleus and then that's where translation happens.

03:24 Whereas because in prokaryotes, you do not have that division of the nucleus that is not there, the ribosome can bind to the mrna right away and start translating it into a protein.

03:38 Okay...

Please give Ace some feedback