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Rna splicing

2012-10-21T12:33:19Z

110102193:

Splicing is the process in which [[Pre-mRNA|pre-mRNA]] is modified by the removal of [[Intron|introns]] to form [[MRNA|mRNA]], comprised of joined [[Exon|exons]]. I[[Intron|ntrons]] normally exist within the protein-coding sequences within the [[Genome|genome]]. Splicing is a neccessary step in many [[Eukaryotic|eukaryotic]] cells for [[Transcription|transcription]], in order for them to form functioning proteins by the secondary process of [[Translation|translation]] of the cell's mRNA. Typically, splicing is achieved through a series of reactions, catalyzed by a spliceosome, a large complex of five small nuclear ribonucleoproteins (snRNPs), however self-splicing introns do exist for introns that form ribozymes, where the function of the spliceosome is performed by the RNA alone. Although splicing exists throughout the kingdoms of life, the extent and type difers greatly. For example, although common in many eukaryotic organisms, splicing occurs rarely in [[Prokaryotes|prokaryotes]] and lacks a spliceosomal pathway.

Rna splicing

2012-10-21T12:24:49Z

110102193:

Splicing is the process in which [[Pre-mRNA|pre-mRNA]] is modified by the removal of [[Intron|introns]] to form [[MRNA|mRNA]], comprising only joined [[Exon|exons]]. These [[Intron|introns]] normally exist within protein-coding sequences within the [[Genome|genome]]. Splicing is neccessary in many [[Eukaryotic|eukaryotic]] cells for [[Transcription|transcription]], in order for them to form functioning proteins by the secondary process of [[Translation|translation]] of the cell's mRNA. Typically, splicing is achieved through a series of reactions, catalyzed by a spliceosome, a large complex of five small nuclear ribonucleoproteins (snRNPs), however self-splicing introns do exist for introns that form ribozymes, where the function of the spliceosome is performed by the RNA alone. Although splicing exists throughout the kingdoms of life, the extent and type difers greatly. For example, although common in many eukaryotic organisms, splicing occurs rarely in [[Prokaryotes|prokaryotes]] and lacks a spliceosomal pathway.

Rna splicing

2012-10-21T12:14:41Z

110102193: Created page with "Splicing is the process in which pre-mRNA is modified by the removal of introns to form mRNA, comprising only joined exons. These introns normally exist within protein-coding seq..."

Splicing is the process in which pre-mRNA is modified by the removal of introns to form mRNA, comprising only joined exons. These introns normally exist within protein-coding sequences within the genome. Splicing is neccessary in many eukaryiotic cells for transription, in order for them to form functioning proteins by the secondary process of translation of the cell's mRNA. Typically, splicing is acheived through a series of reactions, catalysed by a spliceosome, a large complex of five small nuclear ribonucleoproteins (snRNPs), however self-splicing introns do exist for introns that form ribozymes, where the function of the spliceosome is performed by the RNA alone. Although splicing exists throughout the kingdoms of life, the extent and type difers greatly. For example, although common in many eukaryotic organisms, splicing occurs rarely in prokaryotes and lacks a spliceosomal pathway.

Operon

2011-12-01T16:50:50Z

110102193:

Commonly known to exist in the [[Genome|genomes]] of [[Prokaryotes|prokaryotes]] since the 1940s, an operon is a unit of [[DNA|DNA]], comprised of a number of clustered [[Gene|genes]] that are often related by function<ref>Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. The [[Gene|genes]] in operons are [[Transcription|transcribed]] together by a single [[Promoter|promoter]] into the same [[MRNA|mRNA]] strand, before they are [[Translation|translated]] into separate [[Protein|proteins]] <ref>Lodish, Harvey; Zipursky, Lawrence; Matsudaira, Paul; Baltimore, David; Darnel, James (2000). "Chapter 9: Molecular Definition of a Gene". Molecular Cell Biology. W. H. Freeman. ISBN 0-7167-3136-2</ref> , allowing co-ordination of [[Protein synthesis|protein synthesis]] in response to environmental factors, thereby conserving the [[Prokaryotes|cells]] energy<ref>↑ Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. [[Gene|Genes]] in an operon are thus either [[Transcription|transcribed]] together or not at all, such as the [[Lac operon|lac operon]] in E. coli that is used to [[Hydrolysis|hydrolyse]] [[Lactose|lactose]] into [[Glucose|glucose]] and [[Galactose|galactose]].

[[Image:Lac_Operon.GIF|frame|right|The Lac Operon of E.coli]]

=== References ===

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File:Lac Operon.GIF

2011-12-01T16:48:35Z

110102193: The Lac-operon in E.coli

The Lac-operon in E.coli

Operon

2011-12-01T16:43:45Z

110102193:

Commonly known to exist in the [[Genome|genomes]] of [[Prokaryotes|prokaryotes]] since the 1940s, an operon is a unit of [[DNA|DNA]], comprised of a number of clustered [[Gene|genes]] that are often related by function<ref>Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. The [[Gene|genes]] in operons are [[Transcription|transcribed]] together by a single [[Promoter|promoter]] into the same [[MRNA|mRNA]] strand, before they are [[Translation|translated]] into separate [[Protein|proteins]] <ref>Lodish, Harvey; Zipursky, Lawrence; Matsudaira, Paul; Baltimore, David; Darnel, James (2000). "Chapter 9: Molecular Definition of a Gene". Molecular Cell Biology. W. H. Freeman. ISBN 0-7167-3136-2</ref> , allowing co-ordination of [[Protein synthesis|protein synthesis]] in response to environmental factors, thereby conserving the [[Prokaryotes|cells]] energy<ref>↑ Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. [[Gene|Genes]] in an operon are thus either [[Transcription|transcribed]] together or not at all, such as the [[Lac operon|lac operon]] in E. coli that is used to [[Hydrolysis|hydrolyse]] [[Lactose|lactose]] into [[Glucose|glucose]] and [[Galactose|galactose]].

 

=== References ===

<references />

<references />

Operon

2011-12-01T16:41:05Z

110102193:

Commonly known to exist in the [[Genome|genomes]] of [[Prokaryotes|prokaryotes]] since the 1940s, an operon is a unit of [[DNA|DNA]], comprised of a number of clustered [[Gene|genes]] that are often related by function<ref>Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. The [[Gene|genes]] in operons are [[Transcription|transcribed]] together by a single [[Promoter|promoter]] into the same [[MRNA|mRNA]] strand, before they are [[Translation|translated]] into separate [[Protein|proteins]] , allowing co-ordination of [[Protein synthesis|protein synthesis]] in response to environmental factors, thereby conserving the [[Prokaryotes|cells]] energy<ref>↑ Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. [[Gene|Genes]] in an operon are thus either [[Transcription|transcribed]] together or not at all, such as the [[Lac operon|lac operon]] in E. coli that is used to [[Hydrolysis|hydrolyse]] [[Lactose|lactose]] into [[Glucose|glucose]] and [[Galactose|galactose]].

 

=== References ===

<references />

Operon

2011-12-01T16:40:33Z

110102193:

Commonly known to exist in the [[Genome|genomes]] of [[Prokaryotes|prokaryotes]] since the 1940s, an operon is a unit of [[DNA|DNA]], comprised of a number of clustered [[Gene|genes]] that are often related by function<ref>Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. The [[Gene|genes]] in operons are [[Transcription|transcribed]] together by a single [[Promoter|promoter]] into the same [[MRNA|mRNA]] strand, before they are [[Translation|translated]] into separate [[Protein|proteins]] [[Promoter|<ref>Sadava, David et al. (2009). Life: The Science of Biology (9th ed.). Macmillan. p. 349. ISBN 9781429219624.</ref>]], allowing co-ordination of [[Protein synthesis|protein synthesis]] in response to environmental factors, thereby conserving the [[Prokaryotes|cells]] energy<ref>↑ Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. [[Gene|Genes]] in an operon are thus either [[Transcription|transcribed]] together or not at all, such as the [[Lac operon|lac operon]] in E. coli that is used to [[Hydrolysis|hydrolyse]] [[Lactose|lactose]] into [[Glucose|glucose]] and [[Galactose|galactose]].

 

=== References ===

<references />

Operon

2011-12-01T16:40:14Z

110102193:

Commonly known to exist in the [[Genome|genomes]] of [[Prokaryotes|prokaryotes]] since the 1940s, an operon is a unit of [[DNA|DNA]], comprised of a number of clustered [[Gene|genes]] that are often related by function<ref>Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. The [[Gene|genes]] in operons are [[Transcription|transcribed]] together by a single [[Promoter|promoter]] into the same [[MRNA|mRNA]] strand, before they are [[Translation|translated]] into separate [[Protein|proteins]][[Promoter|<ref>Sadava, David et al. (2009). Life: The Science of Biology (9th ed.). Macmillan. p. 349. ISBN 9781429219624.</ref>]], allowing co-ordination of [[Protein synthesis|protein synthesis]] in response to environmental factors, thereby conserving the [[Prokaryotes|cells]] energy<ref>↑ Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. [[Gene|Genes]] in an operon are thus either [[Transcription|transcribed]] together or not at all, such as the [[Lac operon|lac operon]] in E. coli that is used to [[Hydrolysis|hydrolyse]] [[Lactose|lactose]] into [[Glucose|glucose]] and [[Galactose|galactose]].

 

=== References ===

<references />

Operon

2011-12-01T16:28:51Z

110102193:

Commonly known to exist in the [[Genome|genomes]] of [[Prokaryotes|prokaryotes]] since the 1940s, an operon is a unit of [[DNA|DNA]], comprised of a number of clustered [[Gene|genes]] that are often related by function<ref>Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. The [[Gene|genes]] in operons are [[Transcription|transcribed]] together by a single [[Promoter|promoter]] into the same [[MRNA|mRNA]] strand, before they are [[Translation|translated]] into separate [[Protein|proteins]][[Promoter|<ref>Sadava, David et al. (2009). Life: The Science of Biology (9th ed.). Macmillan. p. 349. ISBN 9781429219624.</ref>]], allowing co-ordination of [[Protein synthesis|protein synthesis]] in response to environmental factors, thereby conserving the [[Prokaryotes|cells]] energy. [[Gene|Genes]] in an operon are thus either [[Transcription|transcribed]] together or not at all, such as the[[Lac operon|lac operon]] in E. coli that is used to [[Hydrolysis|hydrolyse]] [[Lactose|lactose]] into [[Glucose|glucose]] and[[Galactose|galactose]].

 

=== References ===

<references />

Operon

2011-12-01T16:26:24Z

110102193:

Commonly known to exist in the [[Genome|genomes]] of [[Prokaryotes|prokaryotes]] since the 1940s, an operon is a unit of [[DNA|DNA]], comprised of a number of clustered [[Gene|genes]] that are often related by function<ref>Encyclopedia Britannica, Operon. Available at: http://www.britannica.com/EBchecked/topic/429974/operon</ref>. The [[Gene|genes]] in operons are [[Transcription|transcribed]] together by a single [[Promoter|promoter]] into the same [[MRNA|mRNA]] strand, before they are [[Translation|translated]] into separate [[Protein|proteins]], allowing co-ordination of [[Protein synthesis|protein synthesis]] in response to environmental factors, thereby conserving the [[Prokaryotes|cells]] energy. [[Gene|Genes]] in an operon are thus either [[Transcription|transcribed]] together or not at all, such as the[[Lac operon|lac operon]] in E. coli that is used to [[Hydrolysis|hydrolyse]] [[Lactose|lactose]] into [[Glucose|glucose]] and[[Galactose|galactose]].

=== References ===

<references />

Operon

2011-12-01T16:17:10Z

110102193:

 Commonly known to exist in the [[Genome|genomes]] of [[Prokaryotes|prokaryotes]] since the 1940s, an operon is a unit of [[DNA|DNA]], comprised of a number of clustered [[Gene|genes]] that are often related by function. The [[Gene|genes]] in operons are [[Transcription|transcribed]] together by a single [[Promoter|promoter]] into the same [[MRNA|mRNA]] strand, before they are [[Translation|translated]] into separate [[Protein|proteins]], allowing co-ordination of [[Protein_synthesis|protein synthesis]] in response to environmental factors, thereby conserving the [[Prokaryotes|cells]] energy. [[Gene|Genes]] in an operon are thus either [[Transcription|transcribed]] together or not at all, such as the[[Lac_operon|lac operon]] in E. coli that is used to [[Hydrolysis|hydrolyse]] [[Lactose|lactose]] into [[Glucose|glucose]] and[[Galactose|galactose]].

Operon

2011-12-01T16:11:05Z

110102193: Created page with " Commonly known to exist in the genomes of prokaryotes since the 1940s, an operon is a unit of DNA, comprised of a number of clustered genes that are often related by functi..."

 Commonly known to exist in the genomes of prokaryotes since the 1940s, an operon is a unit of DNA, comprised of a number of clustered genes that are often related by function. The genes in operons are transcribed together by a single promoter into the same mRNA strand, before they are translated into separate proteins, allowing co-ordination of protein synthesis in response to environmental factors, thereby conserving the cells energy. Genes in an operon are thus either transcribed together or not at all, such as the lac operon in E. coli that is used to hydrolyse lactose into glucose and galactose.