Transposons in aging - Revision history

Andrea: /* Transposons in laminopathic diseases */

2023-03-26T11:41:29Z

Transposons in laminopathic diseases

← Older revision		Revision as of 11:41, 26 March 2023
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	===Transposons in laminopathic diseases===		===Transposons in laminopathic diseases===
	Laminopathies are a type of rare genetic disorders that arise from mutations in nuclear lamina genes, which are important to maintain fibrillar networks in the nucleus and to regulate events in chromatin organisation. A reduction in the expression of some lamin genes is also associated with aging and to a deregulation of transposable elements.<ref>Andrenacci, D., Cavaliere, V., & Lattanzi, G. (2020). The role of transposable elements activity in aging and their possible involvement in laminopathic diseases. ''Ageing Research Reviews'', ''57'', 100995. doi: 10.1016/j.arr.2019.100995</ref> ~~(*to expand)~~		Laminopathies are a type of rare genetic disorders that arise from mutations in nuclear lamina genes, which are important to maintain fibrillar networks in the nucleus and to regulate events in chromatin organisation. A reduction in the expression of some lamin genes is also associated with aging and to a deregulation of transposable elements.<ref>Andrenacci, D., Cavaliere, V., & Lattanzi, G. (2020). The role of transposable elements activity in aging and their possible involvement in laminopathic diseases. ''Ageing Research Reviews'', ''57'', 100995. doi: 10.1016/j.arr.2019.100995</ref>

	<references />		<references />
	[[Category:Main list]]		[[Category:Main list]]
	[[Category:Aging pathways and hallmarks]]		[[Category:Aging pathways and hallmarks]]

Andrea: category change

2022-12-27T21:53:37Z

category change

← Older revision		Revision as of 21:53, 27 December 2022
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	<references />		<references />
	[[Category:~~Longevity~~]]		[[Category:Main list]]
			[[Category:Aging pathways and hallmarks]]

Wurstuk: removed comments

2022-11-12T15:08:23Z

removed comments

← Older revision		Revision as of 15:08, 12 November 2022
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	===DNA-only transposons===		===DNA-only transposons===
	This type of transposons, and unlike retrotransposons, are able to translocate from one chromosome to another. They code themselves for transposase enzymes, which facilitates the transferring process. DNA-only transposons do not transfer very frequently and it is unknown what process is responsible for their action.		This type of transposons, and unlike retrotransposons, are able to translocate from one chromosome to another. They code themselves for transposase enzymes, which facilitates the transferring process. DNA-only transposons do not transfer very frequently and it is unknown what process is responsible for their action.

	<code>Anton:</code> ''As far as I know the major difference between DNA (without only) transposons and retrotransposons is, that DNA transposons transpose via a "cut-and-paste" mechanism and retrotransposons via a "copy-and-paste" mechanism. I think there are numerous great illustrations of this and I can look them up later :)''

	===Retrotransposons===		===Retrotransposons===
	These are the most common class of transposons in humans. They are sections of DNA inserted into the chromosome, but never jump out of it to other chromosomes. Retrotansposons transcribe their sequence of DNA into RNA copies and require the enzyme reverse transcriptase to then be converted into double-stranded DNA, which will then insert themselves elsewhere in the genome. They are named after retroviruses such as HIV, which also require reverse transcriptase to be inserted into the host chromosomes and replicate. Retrotransposons have had an important role in evolution by generating a large amount of the repetitive DNA sequences, and much of the non-coding "junk" DNA consists of this type of transposons.		These are the most common class of transposons in humans. They are sections of DNA inserted into the chromosome, but never jump out of it to other chromosomes. Retrotansposons transcribe their sequence of DNA into RNA copies and require the enzyme reverse transcriptase to then be converted into double-stranded DNA, which will then insert themselves elsewhere in the genome. They are named after retroviruses such as HIV, which also require reverse transcriptase to be inserted into the host chromosomes and replicate. Retrotransposons have had an important role in evolution by generating a large amount of the repetitive DNA sequences, and much of the non-coding "junk" DNA consists of this type of transposons.

	~~<code>Anton:</code> ''I think [[wikipedia:Long_interspersed_nuclear_element\|Lines]] are also quite important transposons for humans (esp. LINE1) but I don't know if they are important for aging.''~~

	==Transposons in aging==		==Transposons in aging==

Andrea: Added to articles list

2022-10-28T12:26:38Z

Added to articles list

← Older revision		Revision as of 12:26, 28 October 2022
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	[[File:Transposition mechanism.png\|thumb\|[Write caption later]]]		[[File:Transposition mechanism.png\|thumb\|[Write caption later]]]
	Transposons were first discovered in corn (maize) by Barbara McClintock during the decades of 1940-50s, for which she won the Nobel Prize of Physiology or Medicine in 1983.<ref>McClintock, B. (1931). The Order of the Genes C, Sh and Wx in Zea Mays with Reference to a Cytologically Known Point in the Chromosome. ''Proceedings Of The National Academy Of Sciences'', ''17''(8), 485-491. doi: 10.1073/pnas.17.8.485</ref><ref>McClintock, B. Mutable loci in maize. Carnegie Institution of Washington Yearbook '''50''', 174–181 (1951).[https://profiles.nlm.nih.gov/spotlight/ll]</ref><ref>Ravindran, S. (2012). Barbara McClintock and the discovery of jumping genes. ''Proceedings Of The National Academy Of Sciences'', ''109''(50), 20198-20199. doi: 10.1073/pnas.1219372109</ref>		Transposons were first discovered in corn (maize) by Barbara McClintock during the decades of 1940-50s, for which she won the Nobel Prize of Physiology or Medicine in 1983.<ref>McClintock, B. (1931). The Order of the Genes C, Sh and Wx in Zea Mays with Reference to a Cytologically Known Point in the Chromosome. ''Proceedings Of The National Academy Of Sciences'', ''17''(8), 485-491. doi: 10.1073/pnas.17.8.485</ref><ref>McClintock, B. Mutable loci in maize. Carnegie Institution of Washington Yearbook '''50''', 174–181 (1951).[https://profiles.nlm.nih.gov/spotlight/ll]</ref><ref>Ravindran, S. (2012). Barbara McClintock and the discovery of jumping genes. ''Proceedings Of The National Academy Of Sciences'', ''109''(50), [tel:20198-20199 20198-20199]. doi: 10.1073/pnas.1219372109</ref>

	Transposons, also called "jumping genes", are genes not fixed in location and are capable of changing position within the genome. Transposase enzymes bind to the end of transposon elements and catalyze their movement to other parts of the genome. Transposons have no known direct functions, but they can sometimes result in ''de novo'' mutations or changes in genome size. This can result in dangerous modifications to the genome, as they might lead to inactivation of important sequences, aberrant control of genes or tumourogenesis.		Transposons, also called "jumping genes", are genes not fixed in location and are capable of changing position within the genome. Transposase enzymes bind to the end of transposon elements and catalyze their movement to other parts of the genome. Transposons have no known direct functions, but they can sometimes result in ''de novo'' mutations or changes in genome size. This can result in dangerous modifications to the genome, as they might lead to inactivation of important sequences, aberrant control of genes or tumourogenesis.
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	<references />		<references />
			[[Category:Longevity]]

Wurstuk: Added an illustration about transposition mechanisms

2022-10-27T15:56:43Z

Added an illustration about transposition mechanisms

← Older revision		Revision as of 15:56, 27 October 2022
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			[[File:Transposition mechanism.png\|thumb\|[Write caption later]]]
	Transposons were first discovered in corn (maize) by Barbara McClintock during the decades of 1940-50s, for which she won the Nobel Prize of Physiology or Medicine in 1983.<ref>McClintock, B. (1931). The Order of the Genes C, Sh and Wx in Zea Mays with Reference to a Cytologically Known Point in the Chromosome. ''Proceedings Of The National Academy Of Sciences'', ''17''(8), 485-491. doi: 10.1073/pnas.17.8.485</ref><ref>McClintock, B. Mutable loci in maize. Carnegie Institution of Washington Yearbook '''50''', 174–181 (1951).[https://profiles.nlm.nih.gov/spotlight/ll]</ref><ref>Ravindran, S. (2012). Barbara McClintock and the discovery of jumping genes. ''Proceedings Of The National Academy Of Sciences'', ''109''(50), 20198-20199. doi: 10.1073/pnas.1219372109</ref>		Transposons were first discovered in corn (maize) by Barbara McClintock during the decades of 1940-50s, for which she won the Nobel Prize of Physiology or Medicine in 1983.<ref>McClintock, B. (1931). The Order of the Genes C, Sh and Wx in Zea Mays with Reference to a Cytologically Known Point in the Chromosome. ''Proceedings Of The National Academy Of Sciences'', ''17''(8), 485-491. doi: 10.1073/pnas.17.8.485</ref><ref>McClintock, B. Mutable loci in maize. Carnegie Institution of Washington Yearbook '''50''', 174–181 (1951).[https://profiles.nlm.nih.gov/spotlight/ll]</ref><ref>Ravindran, S. (2012). Barbara McClintock and the discovery of jumping genes. ''Proceedings Of The National Academy Of Sciences'', ''109''(50), 20198-20199. doi: 10.1073/pnas.1219372109</ref>

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	Retrotransposons, the most common type of transposons, proceeds via an RNA intermediate that can be targeted by RNA interference (RNAi) mechanisms, which then degrade these molecules to prevent their expression. Thus, RNAi is postulated to have evolved as a protective mechanism against retroviruses and endogenous retrotransposons in order to prevent their excessive activity.		Retrotransposons, the most common type of transposons, proceeds via an RNA intermediate that can be targeted by RNA interference (RNAi) mechanisms, which then degrade these molecules to prevent their expression. Thus, RNAi is postulated to have evolved as a protective mechanism against retroviruses and endogenous retrotransposons in order to prevent their excessive activity.

	== Types of transposons ==		==Types of transposons==
	There are several types of transposons:		There are several types of transposons:

	=== DNA-only transposons ===		===DNA-only transposons===
	This type of transposons, and unlike retrotransposons, are able to translocate from one chromosome to another. They code themselves for transposase enzymes, which facilitates the transferring process. DNA-only transposons do not transfer very frequently and it is unknown what process is responsible for their action.		This type of transposons, and unlike retrotransposons, are able to translocate from one chromosome to another. They code themselves for transposase enzymes, which facilitates the transferring process. DNA-only transposons do not transfer very frequently and it is unknown what process is responsible for their action.

	<code>Anton:</code> ''As far as I know the major difference between DNA (without only) transposons and retrotransposons is, that DNA transposons transpose via a "cut-and-paste" mechanism and retrotransposons via a "copy-and-paste" mechanism. I think there are numerous great illustrations of this and I can look them up later :)''		<code>Anton:</code> ''As far as I know the major difference between DNA (without only) transposons and retrotransposons is, that DNA transposons transpose via a "cut-and-paste" mechanism and retrotransposons via a "copy-and-paste" mechanism. I think there are numerous great illustrations of this and I can look them up later :)''

	=== Retrotransposons ===		===Retrotransposons===
	These are the most common class of transposons in humans. They are sections of DNA inserted into the chromosome, but never jump out of it to other chromosomes. Retrotansposons transcribe their sequence of DNA into RNA copies and require the enzyme reverse transcriptase to then be converted into double-stranded DNA, which will then insert themselves elsewhere in the genome. They are named after retroviruses such as HIV, which also require reverse transcriptase to be inserted into the host chromosomes and replicate. Retrotransposons have had an important role in evolution by generating a large amount of the repetitive DNA sequences, and much of the non-coding "junk" DNA consists of this type of transposons.		These are the most common class of transposons in humans. They are sections of DNA inserted into the chromosome, but never jump out of it to other chromosomes. Retrotansposons transcribe their sequence of DNA into RNA copies and require the enzyme reverse transcriptase to then be converted into double-stranded DNA, which will then insert themselves elsewhere in the genome. They are named after retroviruses such as HIV, which also require reverse transcriptase to be inserted into the host chromosomes and replicate. Retrotransposons have had an important role in evolution by generating a large amount of the repetitive DNA sequences, and much of the non-coding "junk" DNA consists of this type of transposons.

	<code>Anton:</code> ''I think [[wikipedia:Long_interspersed_nuclear_element\|Lines]] are also quite important transposons for humans (esp. LINE1) but I don't know if they are important for aging.''		<code>Anton:</code> ''I think [[wikipedia:Long_interspersed_nuclear_element\|Lines]] are also quite important transposons for humans (esp. LINE1) but I don't know if they are important for aging.''

	== Transposons in aging ==		==Transposons in aging==

	=== Transposons as a cause of aging ===		=== Transposons as a cause of aging===
	Transposons are hypothesized to be a cause of aging due to some of their properties.<ref name=":0">Murray, V. (1990). Are transposons a cause of ageing?. ''Mutation Research/Dnaging'', ''237''(2), 59-63. doi: 10.1016/0921-8734(90)90011-f</ref> This hypothesis is based on the observation that duplication of genes during transposition, the process in which a transposon element moves to another location in the genome, might lead to inactivation of essential genes or to cause aberrant function. Thus dysfunctional processes during aging have been proposed to arise as a consequence of the large amount of transposon elements present in "junk" DNA regions, and might potentially explain the properties of senescent cells.<ref name=":0" />		Transposons are hypothesized to be a cause of aging due to some of their properties.<ref name=":0">Murray, V. (1990). Are transposons a cause of ageing?. ''Mutation Research/Dnaging'', ''237''(2), 59-63. doi: 10.1016/0921-8734(90)90011-f</ref> This hypothesis is based on the observation that duplication of genes during transposition, the process in which a transposon element moves to another location in the genome, might lead to inactivation of essential genes or to cause aberrant function. Thus dysfunctional processes during aging have been proposed to arise as a consequence of the large amount of transposon elements present in "junk" DNA regions, and might potentially explain the properties of senescent cells.<ref name=":0" />

	=== Transposons in laminopathic diseases ===		===Transposons in laminopathic diseases===
	Laminopathies are a type of rare genetic disorders that arise from mutations in nuclear lamina genes, which are important to maintain fibrillar networks in the nucleus and to regulate events in chromatin organisation. A reduction in the expression of some lamin genes is also associated with aging and to a deregulation of transposable elements.<ref>Andrenacci, D., Cavaliere, V., & Lattanzi, G. (2020). The role of transposable elements activity in aging and their possible involvement in laminopathic diseases. ''Ageing Research Reviews'', ''57'', 100995. doi: 10.1016/j.arr.2019.100995</ref> (*to expand)		Laminopathies are a type of rare genetic disorders that arise from mutations in nuclear lamina genes, which are important to maintain fibrillar networks in the nucleus and to regulate events in chromatin organisation. A reduction in the expression of some lamin genes is also associated with aging and to a deregulation of transposable elements.<ref>Andrenacci, D., Cavaliere, V., & Lattanzi, G. (2020). The role of transposable elements activity in aging and their possible involvement in laminopathic diseases. ''Ageing Research Reviews'', ''57'', 100995. doi: 10.1016/j.arr.2019.100995</ref> (*to expand)

			<references />

Wurstuk: only commented

2022-10-26T16:42:50Z

only commented

← Older revision		Revision as of 16:42, 26 October 2022
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	=== DNA-only transposons ===		=== DNA-only transposons ===
	This type of transposons, and unlike retrotransposons, are able to translocate from one chromosome to another. They code themselves for transposase enzymes, which facilitates the transferring process. DNA-only transposons do not transfer very frequently and it is unknown what process is responsible for their action.		This type of transposons, and unlike retrotransposons, are able to translocate from one chromosome to another. They code themselves for transposase enzymes, which facilitates the transferring process. DNA-only transposons do not transfer very frequently and it is unknown what process is responsible for their action.

			<code>Anton:</code> ''As far as I know the major difference between DNA (without only) transposons and retrotransposons is, that DNA transposons transpose via a "cut-and-paste" mechanism and retrotransposons via a "copy-and-paste" mechanism. I think there are numerous great illustrations of this and I can look them up later :)''

	=== Retrotransposons ===		=== Retrotransposons ===
	These are the most common class of transposons in humans. They are sections of DNA inserted into the chromosome, but never jump out of it to other chromosomes. Retrotansposons transcribe their sequence of DNA into RNA copies and require the enzyme reverse transcriptase to then be converted into double-stranded DNA, which will then insert themselves elsewhere in the genome. They are named after retroviruses such as HIV, which also require reverse transcriptase to be inserted into the host chromosomes and replicate. Retrotransposons have had an important role in evolution by generating a large amount of the repetitive DNA sequences, and much of the non-coding "junk" DNA consists of this type of transposons.		These are the most common class of transposons in humans. They are sections of DNA inserted into the chromosome, but never jump out of it to other chromosomes. Retrotansposons transcribe their sequence of DNA into RNA copies and require the enzyme reverse transcriptase to then be converted into double-stranded DNA, which will then insert themselves elsewhere in the genome. They are named after retroviruses such as HIV, which also require reverse transcriptase to be inserted into the host chromosomes and replicate. Retrotransposons have had an important role in evolution by generating a large amount of the repetitive DNA sequences, and much of the non-coding "junk" DNA consists of this type of transposons.

			<code>Anton:</code> ''I think [[wikipedia:Long_interspersed_nuclear_element\|Lines]] are also quite important transposons for humans (esp. LINE1) but I don't know if they are important for aging.''

	== Transposons in aging ==		== Transposons in aging ==

Andrea: Created and added content to new page

2022-10-10T18:37:02Z

Created and added content to new page

New page

Transposons were first discovered in corn (maize) by Barbara McClintock during the decades of 1940-50s, for which she won the Nobel Prize of Physiology or Medicine in 1983.<ref>McClintock, B. (1931). The Order of the Genes C, Sh and Wx in Zea Mays with Reference to a Cytologically Known Point in the Chromosome. ''Proceedings Of The National Academy Of Sciences'', ''17''(8), 485-491. doi: 10.1073/pnas.17.8.485</ref><ref>McClintock, B. Mutable loci in maize. Carnegie Institution of Washington Yearbook '''50''', 174–181 (1951).[https://profiles.nlm.nih.gov/spotlight/ll]</ref><ref>Ravindran, S. (2012). Barbara McClintock and the discovery of jumping genes. ''Proceedings Of The National Academy Of Sciences'', ''109''(50), 20198-20199. doi: 10.1073/pnas.1219372109</ref>

Transposons, also called "jumping genes", are genes not fixed in location and are capable of changing position within the genome. Transposase enzymes bind to the end of transposon elements and catalyze their movement to other parts of the genome. Transposons have no known direct functions, but they can sometimes result in ''de novo'' mutations or changes in genome size. This can result in dangerous modifications to the genome, as they might lead to inactivation of important sequences, aberrant control of genes or tumourogenesis.

Retrotransposons, the most common type of transposons, proceeds via an RNA intermediate that can be targeted by RNA interference (RNAi) mechanisms, which then degrade these molecules to prevent their expression. Thus, RNAi is postulated to have evolved as a protective mechanism against retroviruses and endogenous retrotransposons in order to prevent their excessive activity.

== Types of transposons ==
There are several types of transposons:

=== DNA-only transposons ===
This type of transposons, and unlike retrotransposons, are able to translocate from one chromosome to another. They code themselves for transposase enzymes, which facilitates the transferring process. DNA-only transposons do not transfer very frequently and it is unknown what process is responsible for their action.

=== Retrotransposons ===
These are the most common class of transposons in humans. They are sections of DNA inserted into the chromosome, but never jump out of it to other chromosomes. Retrotansposons transcribe their sequence of DNA into RNA copies and require the enzyme reverse transcriptase to then be converted into double-stranded DNA, which will then insert themselves elsewhere in the genome. They are named after retroviruses such as HIV, which also require reverse transcriptase to be inserted into the host chromosomes and replicate. Retrotransposons have had an important role in evolution by generating a large amount of the repetitive DNA sequences, and much of the non-coding "junk" DNA consists of this type of transposons.

== Transposons in aging ==

=== Transposons as a cause of aging ===
Transposons are hypothesized to be a cause of aging due to some of their properties.<ref name=":0">Murray, V. (1990). Are transposons a cause of ageing?. ''Mutation Research/Dnaging'', ''237''(2), 59-63. doi: 10.1016/0921-8734(90)90011-f</ref> This hypothesis is based on the observation that duplication of genes during transposition, the process in which a transposon element moves to another location in the genome, might lead to inactivation of essential genes or to cause aberrant function. Thus dysfunctional processes during aging have been proposed to arise as a consequence of the large amount of transposon elements present in "junk" DNA regions, and might potentially explain the properties of senescent cells.<ref name=":0" />

=== Transposons in laminopathic diseases ===
Laminopathies are a type of rare genetic disorders that arise from mutations in nuclear lamina genes, which are important to maintain fibrillar networks in the nucleus and to regulate events in chromatin organisation. A reduction in the expression of some lamin genes is also associated with aging and to a deregulation of transposable elements.<ref>Andrenacci, D., Cavaliere, V., & Lattanzi, G. (2020). The role of transposable elements activity in aging and their possible involvement in laminopathic diseases. ''Ageing Research Reviews'', ''57'', 100995. doi: 10.1016/j.arr.2019.100995</ref> (*to expand)