2,851
edits
Hallmarks of Aging: Difference between revisions
→The Hallmarks in Detail
| Line 187: | Line 187: | ||
|Telomere shortening is associated with a variety of human diseases, including pulmonary fibrosis, dyskeratosis congenita, and aplastic anemia, often linked to deficiencies in telomerase or shelterin components{{pmid|22965356}}. | |Telomere shortening is associated with a variety of human diseases, including pulmonary fibrosis, dyskeratosis congenita, and aplastic anemia, often linked to deficiencies in telomerase or shelterin components{{pmid|22965356}}. | ||
|- | |- | ||
| rowspan=" | | rowspan="4" style="text-align:center; background-color:hsla(180, 100%, 85%);" |[[File:Epigenome-transparent-upscale.png|frameless|85x85px]] | ||
| rowspan=" | | rowspan="4" style="background-color:hsla(180, 100%, 85%);" |'''[[Epigenetic Alterations|Epigenetic alterations]]''' | ||
| style="background-color:hsla(180, 100%, 85%);" |'''Histone modifications''' are a type of epigenetic alteration that play a crucial role in regulating gene expression. Histones are proteins around which DNA is wrapped in eukaryotic cells, forming a structure known as a nucleosome. These modifications occur primarily at the tails of histone proteins and influence how tightly or loosely DNA is wound around the histones, affecting the accessibility of the DNA to various cellular machinery for processes like transcription, replication, and repair. | | style="background-color:hsla(180, 100%, 85%);" |'''Histone modifications''' are a type of epigenetic alteration that play a crucial role in regulating gene expression. Histones are proteins around which DNA is wrapped in eukaryotic cells, forming a structure known as a nucleosome. These modifications occur primarily at the tails of histone proteins and influence how tightly or loosely DNA is wound around the histones, affecting the accessibility of the DNA to various cellular machinery for processes like transcription, replication, and repair. | ||
|Chemical changes to histone proteins after they are formed can activate or silence gene expression and regulate the aging process.{{pmid|17320507}} | |Chemical changes to histone proteins after they are formed can activate or silence gene expression and regulate the aging process.{{pmid|17320507}} | ||
| Line 212: | Line 212: | ||
| | | | ||
|- | |- | ||
|''' | |'''Transcriptional alterations''' refer to changes in the process by which genes are expressed into RNA, which can then be translated into proteins. These alterations can influence which genes are turned on or off, the timing of their activation, the amount of RNA produced, and the stability or processing of that RNA. | ||
| | |Aging leads to more transcriptional noise, meaning more random variations in gene activity{{pmid|16791200}}, and also causes irregular production and processing of many mRNAs, the molecules that carry genetic information from DNA for protein creation{{pmid|21668623}}{{pmid|20538013}}. Also miRNAs that is associated with the aging process is affected{{pmid|22660319}}{{pmid|22064465}}. | ||
| | |Expression of several miRNAs increases longevity in [[Drosophila Melanogaster|Drosophila melanogaster]] and [[Nematode Worms (Caenorhabditis Elegans)|C. elegans]]{{pmid|22343898}}{{pmid|23239738}}{{pmid|22294612}}. | ||
| | |Loss of several miRNAs is associated with increase aging in [[Drosophila Melanogaster|Drosophila melanogaster]] and [[Nematode Worms (Caenorhabditis Elegans)|C. elegans]]{{pmid|22343898}}{{pmid|23239738}}{{pmid|22294612}}. | ||
| | | | ||
|- | |- | ||
| style="text-align:center; background-color:hsla(210, 100%, 85%);" |[[File:Stress signaling.png|frameless|95x95px]] | | style="text-align:center; background-color:hsla(210, 100%, 85%);" |[[File:Stress signaling.png|frameless|95x95px]] | ||