Telomerase reverse transcriptase
Encyclopedia
Telomerase reverse transcriptase (abbreviated to TERT, or hTERT in humans) is a catalytic subunit of the enzyme
telomerase
. Its absence (usually as a result of a chromosomal
mutation
) is associated with the disorder Cri du chat
.
Despite their similarities to other RNA-dependent polymerases, telomerases are part of a distinct subgroup of proteins because they are so similar to each other even when they come from diverse organisms. To wit, telomerase lengthens telomeres in DNA
strands, thereby allowing senescent cell
s that would otherwise become postmitotic and undergo apoptosis
to exceed the Hayflick limit
and become potentially immortal, as is often the case with cancerous cells.
Genome-wide association studies suggest TERT is a susceptibility gene for development of many cancers, including lung cancer.
with Ku70, YWHAQ
, Nucleolin
, Ku80, Heat shock protein 90kDa alpha (cytosolic), member A1, MCRS1
and PINX1
.
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
telomerase
Telomerase
Telomerase is an enzyme that adds DNA sequence repeats to the 3' end of DNA strands in the telomere regions, which are found at the ends of eukaryotic chromosomes. This region of repeated nucleotide called telomeres contains non-coding DNA material and prevents constant loss of important DNA from...
. Its absence (usually as a result of a chromosomal
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
mutation
Mutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...
) is associated with the disorder Cri du chat
Cri du chat
Cri du chat syndrome, also known as chromosome 5p deletion syndrome, 5p minus syndrome or Lejeune’s syndrome, is a rare genetic disorder due to a missing part of chromosome 5. Its name is a French term referring to the characteristic cat-like cry of affected children. It was first described by...
.
Despite their similarities to other RNA-dependent polymerases, telomerases are part of a distinct subgroup of proteins because they are so similar to each other even when they come from diverse organisms. To wit, telomerase lengthens telomeres in DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
strands, thereby allowing senescent cell
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
s that would otherwise become postmitotic and undergo apoptosis
Apoptosis
Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...
to exceed the Hayflick limit
Hayflick limit
The Hayflick limit is the number of times a normal cell population will divide before it stops, presumably because the telomeres reach a critical length....
and become potentially immortal, as is often the case with cancerous cells.
Genome-wide association studies suggest TERT is a susceptibility gene for development of many cancers, including lung cancer.
Interactions
Telomerase reverse transcriptase has been shown to interactProtein-protein interaction
Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...
with Ku70, YWHAQ
YWHAQ
14-3-3 protein theta is a protein that in humans is encoded by the YWHAQ gene.-Interactions:YWHAQ has been shown to interact with MEF2D, Bcl-2-associated X protein, CRTC2, C-Raf, Histone deacetylase 5, NRIP1, Protein kinase Mζ, UCP3, PFKFB2, Telomerase reverse transcriptase, Bcl-2-associated death...
, Nucleolin
Nucleolin
Nucleolin is a protein that in humans is encoded by the NCL gene.- Gene :The human NCL gene is located on chromosome 2 and consists of 14 exons with 13 introns and spans approximately 11kb...
, Ku80, Heat shock protein 90kDa alpha (cytosolic), member A1, MCRS1
MCRS1
Microspherule protein 1 is a protein that in humans is encoded by the MCRS1 gene.-Interactions:MCRS1 has been shown to interact with PHC2, Death associated protein 6, NOL1, PINX1 and Telomerase reverse transcriptase.-Further reading:...
and PINX1
PINX1
PIN2-interacting protein 1, also known as PINX1, is a human gene.-Interactions:PINX1 has been shown to interact with MCRS1, TERF1 and Telomerase reverse transcriptase.-Further reading:...
.