What is gene expression? what two stages are involved in gene expression?
Gene expression is a process in which Genes are transcribed into RNA and then translated to make proteins. Gene expression occurs in two major stages. 1) Transcription: In this process, the gene is copied to produce an RNA molecule (a primary transcript) with essentially the same sequence as the gene. Most human genes are divided into exons and introns, and only the exons carry information required for protein synthesis. Most primary transcripts are therefore processed by splicing to remove intron sequences and generate a mature transcript or messenger RNA (m RNA) that only contains exons. 2) Protein synthesis: This stage is also known as "Translation" and is so called because there is no direct correspondence between the nucleotide sequence in DNA (and RNA) and the sequence of amino acids in the protein. In fact, three nucleotides are required to specify one amino acid. The chain of amino acids must fold up to generate the final tertiary structure of the protein.
What are the 2 steps of Gene Expression?
Gene expression requires two steps - Transcription and Translation. Transcription process changes the DNA to an RNA. The Translation process creates a protein out of the RNA. You can find details of the same in the following website: http://www.surfmark.com/viewsm/331IfswJ-kGSIwjK71KT-Q
What is the role of RNA in gene expression?
What is the role of RNA in gene expression?Assuming gene expression for protein production (for RNA structure synthesis, see How are rRNA and tRNA formed?).Short answer: In three distinct steps, various RNA structures in and outside the nucleus do all the work involved (DNA only serves as input data storage):Gene transcription: RNA polymerase (in the nucleus) first transcribes the selected gene (extracts the gene and its “control data” from DNA) to a primary RNA transcript (a messenger RNA (mRNA) molecule).Post-transcriptional mRNA processing, by many different RNA molecules, splicing, cutting, “editing” the transcript, producing a mature mRNA (exported to the cytosol).mRNA translation: The mRNA strand is picked up by a ribosome (rRNA), which translates it into a protein (transfer RNA (tRNA) delivers the needed amino acids to the ribosome).The question — with variations — has been asked before. For details, see these Quora question answers:What's the role of DNA and RNA in protein formation?What are the three roles of RNA in protein synthesis?What are the differences between DNA, mRNA and tRNA?What are the differences between mRNA, tRNA, and rRNA?Why does the cell use mRNA at the ribosome instead of DNA?What function does DNA serve before it is transcribed and used to code for proteins? Why isn't mRNA formed straight away?What is the difference between DNA and RNA with respect to their biological function?What is the main and most vital function of the ribosomes in a plant cell?Transcription and Translation infograph snagged from www.scq.ubc.ca article Changing the Language of DNA.See alsoWikipedia — Transcription (genetics)Wikipedia — Translation (genetics)owlcation.com — Protein Production: A Simple Summary of Transcription and Translationwww.biologicscorp.com — Protein Synthesis vs Protein Productionwww.scq.ubc.ca — Changing the Language of DNAYouTube —From DNA to Protein:
How does gene expression work?
I like this question , It is very simple but to the point.In my opinion, Gene Expression happens instead of directly translating proteins from the genome itself for the following reasons.Protection of The Cellular Genome pool, because , if you think about it, some translated proteins might be Digesting enzymes, that could directly or indirectly dissolve the Genome itself, because, transcription happens in the nucleus (In Eukaryotes) and mRNA transferred to the cytosol afterwards, This separation of compartments protects the genome itself indirectly by separating the site of producing proteins from the genome itself.The Machinery of Gene Expression allow the genome to be read differently, thus, allowing genes to be read at different locations giving different proteins , you can consider this concept as compression of the genome, allowing the genome to act as a compressed tape, that could be decompressed differently each time, giving rise to different proteins, giving the cell room to save more information in the genome with lesser size, of course, In Eukaryotes, there is an additional step of compression happens outside the Nucleus called “RNA Splicing” also allowing one gene to produce different proteins depending upon the mechanism of cutting it later in the cytosol, also , this feature allow the cell to store more information with the same size, making the cell more efficient and compact.I think the previous reasons are enough to teach us that Life is engineered in very smart way larger than by chance alone, this only dictates the presence of Allah (God) the creator of this universe , if we are really smart mammals, just think about it.I hope that helps , thank you.
What are the three types of RNA molecules. What is their function is transcription/translation?
There are three types of RNA: mRNA, rRNA and tARN. + mRNA (messenger RNA) is a segment of RNA is transcribed directly from the DNA. It has a single circuit structure, straight. It functions: communicating genetic information of the gene, to protein synthesis, regulation body condition. + tARN (transfer RNA) as well as RNA is synthesized from the gene. It has the structure: three lobes. - 1: identify the enzyme attached to the corresponding amino acid. - 2: reaction with ribosomes. - 3: bring to the code (anti codon) match and complement the code on mRNA. It has the function: bringing amino acids corresponding to the nucleotide sequence on the mRNA to create polipeptit. + rRNA (ribosomal RNA) single circuit structure. Single circuit structure, has retorted the helix form. It has functions: make up ribosomes, where protein synthesis
Does all types of RNA create only one type of protein which is polypeptide?
Three general classes of RNA moleculesare involved in expressing the genes encoded within a cell's DNA. Messenger RNA (mRNA) molecules carry the codingsequences for protein synthesis and are called transcripts; ribosomal RNA (rRNA)molecules form the core of a cell's ribosomes (the structures in which protein synthesis takes place); and transfer RNA (tRNA) molecules carry amino acids to the ribosomes during protein synthesis. In eukaryotic cells, each class of RNA has its own polymerase, whereas in prokaryotic cells,a single RNA polymerase synthesizes the different class of RNA. Other types of. RNA also exist but are not as well understood, although they appear to playregulatory roles in gene expression and also be involved in protection against invading viruses.mRNA is the most variable class of RNA,and there are literally thousands of different mRNA molecules present in a cell at any given time. Some mRNA molecules are abundant, numbering in the hundreds or thousands, as is often true of transcripts encoding structural proteins. Other mRNAs are quite rare, with perhaps only a single copy present, as is sometimes the case for transcripts that encode signaling proteins. mRNAs also vary in how long-lived they are. In eukaryotes, transcripts for structural proteins may remain intact for over ten hours, whereas transcripts for signaling proteins may be degraded in less than ten minutes.
List 3 types of RNA required for translation. Explain the function of each.?
Three types of RNA required for translation: 1. Messenger RNA- this is a "mirror image" of the DNA encoding the amino acid sequence for the protein specified by the gene. 2. Transfer RNA- This is an RNA molecule that "activates" the amino acid and recognizes the codon specifiying that amino acid in the mRNA sequence. 3. Ribosomal RNA- this is probably RNA that has a structural role in a complex called the ribosome, the "machine" that actually joins amino acids together to make proteins.
What are the three types of RNA?
RNA stands for ribonucleic acid.It is a polymeric molecule that is present in all organisms except in DNA viruses.They are single stranded nucleic acid composed of nucleotides.RNA nucleotides consist of three components namely:Nitrogenous baseFive carbon sugarPhosphate groupRNA nitrogenous bases includes adenine(A), guanine(G) ,cytosine(C) and uracil(U). The five carbon sugar in RNA is ribose. RNA molecules are polymers of nucleotides joined to one another by covalent bond between phosphate of one nucleotide and sugar of another. This linkage is know as Phosphodiester linkage.RNA plays an important role in protein synthesis as it is involved in the transcription,decoding and translation of genetic code to produce proteins.Types of RNAThere are three major types of RNA which occurs in all organisms.They are:Messenger RNA (mRNA)Transfer RNA (tRNA)Ribosomal RNA (Messenger RNAAs the name suggests mRNA carries the genetic information from DNA to the ribosomes. Genetic information on the DNA are transcribed into the mRNA by a process called transcription. The mRNA is always single stranded. It is about 3 to 5 per cent of cell. mRNA serves as template for photosynthesis.Transfer RNAThe tRNA is a small molecule when compared with other type of RNAs. It amounts to about 15 per cent of the cell.The most important function of the tRNA is that it carries aminoacid to the site of protien synthesis.tRNA has a clover leaf like structure and it is synthesized in a small part of DNA. Though tRNA molecule is single strand,it assumes clover leaf like structure through folding. It has four arms namely anticodon arm,D arm, T arm and aminoacid acceptor arm.The acceptor arm carries an aminoacid.The anticodon arm has three anticodon nucleotides,which will join with the complementary codon in mRNA during photosynthesis.D arms main function is that of recognition.In certain tRNA addition to these four arms an extra arm called variable arm occurs.Ribosomal RNARibosomal RNAs are the most stable form of RNA. It constitute 80 percent of the total RNA of the cells.They are produced in the nucleus i.e in nucleolus. These RNA associates with proteins to form ribosomes. These complex structure physically move along an mRNA molecule, catalyze the assembly of amino acids into protien chain.Thank you for reading.
Biology. Gene Expressions and Regulations Table on eukaryotic & prokarotic cells?
Here ill try 1. Gene expression occurs nucleus and cytosol for eukaryotes, as RNA is synthesized in the nucleus and then transported to the cytosol for translation. Gene expression occurs in the cytosol for prokaryotes, because they dont have nucleus.. 2. Prokaryotic gene expression is regulated by either positive or negative control. Negative control consists of feed back inhibition- where the catalytic activity of enzymes is inhibited. Or by a repressor directly interfering with the operator of the gene. Positive control is where an molecule will bind to the repressor to deactivate it, and therefore allow transcription to continue. In Eukaryotes, gene expression can be controlled at 5 levels Genome - This involves gene amplification or deletion, chromatin decondensation or DNA methylation Transcription - eurkaryotes have proximal control elements (located upstream from the core promoter) that bind to regulatory transcription factors that increase the efficiency of the core promoter. They can also have Enhancers which bind activators which will stimulate gene transcription. Or they can have Silencers which bind repressors that inhibit gene transcription. Enhancers and Silencers can be located upstream or downstream from the core promoter. RNA Processing and nuclear export - This includes RNA Splicing and nuclear export. For example a mRNA molecule molecule missing a 5'-cap may not be exported from the nucleus. Translation - The rate mRNA is translated into a polypeptide is regulated by altering the ribosome or by regulating the activity and stablilty of the mRNA. Several possible control points here, including the rate of mRNA degradation. Postranslational Control - after the polypeptide is produced it can be modified in structure or function. 3. Substances involved in gene expression include. RNA Polymerase which binds to the DNA promoter region, triggering teh unwinding of the DNA helix and initiating RNA synthesis and then moves along the DNA elongating the newly synthesized RNA molecule, until it reaches the terminal signal. 3 types of RNA - mRNA, tRNA, rRNA are synthesized and then processed. mRNA transproted to the ribosome and then binds to the mRNA binding site on the ribosome. tRNA bound to an amino acid, binds to the complementary sequence on the mRNA. And the mRNA is fully translated until it reaches a stop codon and the peptide is released.
How many types of RNAs are there?
There are 4 types of RNA, each encoded by its own type of gene:mRNA - Messenger RNA: Encodes amino acid sequence of a polypeptide.tRNA - Transfer RNA: Brings amino acids to ribosomes during translation.rRNA - Ribosomal RNA: With ribosomal proteins, makes up the ribosomes, the organelles that translate the mRNA.