Encyclopedia
Scholarly Community
Encyclopedia
Entry
Video
Image
Journal
Book
News
About
Log in/Sign up
Submit
Entry
Video
Image
Subject:
All Disciplines
Arts & Humanities
Biology & Life Sciences
Business & Economics
Chemistry & Materials Science
Computer Science & Mathematics
Engineering
Environmental & Earth Sciences
Medicine & Pharmacology
Physical Sciences
Public Health & Healthcare
Social Sciences
Sort:
Hottest
Latest
Alphabetical (A-Z)
Alphabetical (Z-A)
Type:
All
Topic Review
Biography
Topic Review
Transcription Factor 21 and Chicken Adipocyte Differentiation
Transcription factor 21 (TCF21) could promote chicken preadipocytes differentiation at least in part via activating MAPK/JNK pathway.
427
21 Dec 2021
Topic Review
Transcription and RNA Editing in Plant Chloroplasts
RNA editing is generally perceived as a repair tool to correct genomic mutation (point mutation) at the transcript level in organelles such as mitochondria and chloroplasts.
676
21 Nov 2022
Topic Review
Transcription
Transcription is the process of copying a segment of DNA into RNA. The segments of DNA transcribed into RNA molecules that can encode proteins are said to produce messenger RNA (mRNA). Other segments of DNA are copied into RNA molecules called non-coding RNAs (ncRNAs). Averaged over multiple cell types in a given tissue, the quantity of mRNA is more than 10 times the quantity of ncRNA (though in particular single cell types ncRNAs may exceed mRNAs). The general preponderance of mRNA in cells is valid even though less than 2% of the human genome can be transcribed into mRNA (Human genome), while at least 80% of mammalian genomic DNA can be actively transcribed (in one or more types of cells), with the majority of this 80% considered to be ncRNA. Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language. During transcription, a DNA sequence is read by an RNA polymerase, which produces a complementary, antiparallel RNA strand called a primary transcript. Transcription proceeds in the following general steps: If the stretch of DNA is transcribed into an RNA molecule that encodes a protein, the RNA is termed messenger RNA (mRNA); the mRNA, in turn, serves as a template for the protein's synthesis through translation. Other stretches of DNA may be transcribed into small non-coding RNAs such as microRNA, transfer RNA (tRNA), small nucleolar RNA (snoRNA), small nuclear RNA (snRNA), or enzymatic RNA molecules called ribozymes as well as larger non-coding RNAs such as ribosomal RNA (rRNA), and long non-coding RNA (lncRNA). Overall, RNA helps synthesize, regulate, and process proteins; it therefore plays a fundamental role in performing functions within a cell. In virology, the term transcription may also be used when referring to mRNA synthesis from an RNA molecule (i.e., equivalent to RNA replication). For instance, the genome of a negative-sense single-stranded RNA (ssRNA -) virus may be a template for a positive-sense single-stranded RNA (ssRNA +)[clarification needed]. This is because the positive-sense strand contains the sequence information needed to translate the viral proteins needed for viral replication. This process is catalyzed by a viral RNA replicase.[clarification needed]
2.8K
14 Apr 2023
Topic Review
Transcranial Electrical Stimulation
Transcranial electrical stimulation (tES) can adjust the membrane potential by applying a weak current on the scalp to change the related nerve activity. In recent years, tES has proven its value in studying the neural processes involved in human behavior. The study of central auditory processes focuses on the analysis of behavioral phenomena, including sound localization, auditory pattern recognition, and auditory discrimination. To our knowledge, studies on the application of tES in the field of hearing and the electrophysiological effects are limited. Therefore, we reviewed the neuromodulatory effect of tES on auditory processing, behavior, and cognitive function and have summarized the physiological effects of tES on the auditory cortex.
589
14 Aug 2020
Topic Review
Transcobalamin Deficiency
Transcobalamin deficiency is a disorder that impairs the transport of cobalamin (also known as vitamin B12) within the body.
359
23 Dec 2020
Topic Review
Transboundary Animal Diseases of Viral Origin
The Transboundary Animal Diseases (TADs) are highly transmissible epidemic diseases of livestock which have the capability for rapid spread to new areas and regions regardless of national borders. The TADs are a major threat to livestock of any nation as they have the potential to cause large-scale damage, staking the food security of the country, and can cripple the nation’s economy significantly by direct loss in the form of disease conditions and deaths in affected population or indirectly due to required counter epizootic measures, loss in trade and probable zoonotic transmission.
873
09 Nov 2022
Topic Review
Trans-Synaptic Neurexin–Neuroligin Interaction
Synapses serve as the interface for the transmission of information between neurons in the central nervous system. The structural and functional characteristics of synapses are highly dynamic, exhibiting extensive plasticity that is shaped by neural activity and regulated primarily by trans-synaptic cell-adhesion molecules (CAMs). Prototypical trans-synaptic CAMs, such as neurexins (Nrxs) and neuroligins (Nlgs), directly regulate the assembly of presynaptic and postsynaptic molecules, including synaptic vesicles, active zone proteins, and receptors. Therefore, the trans-synaptic adhesion mechanisms mediated by Nrx–Nlg interaction can contribute to a range of synaptopathies in the context of pathological pain and other neurological disorders.
606
01 Jul 2022
Topic Review
Trans-Olecranon Fracture-Dislocations
Anterior dislocation of the elbow in which compromise of the ulnohumeral articulation occurs through an often complex injury to the proximal ulna
762
10 Dec 2020
Topic Review
Trans-Fatty Acids
Naturally occurring (fatty acids) FAs usually have the cis-configuration. Nevertheless, under certain conditions (e.g. partial catalytic hydrogenation or enzymatic hydrogenation), a double bond in FAs may change from a cis (Z) to a trans (E) configuration (geometric isomerization) and/or move to other positions in the carbon chain (positional isomerization). TFAs mediate increase of LDL levels and decrease of HDL levels in blood, which may lead to health consequences (e.g. cardiovascular diseases), even if this association is unclear considering the small proportion (about 10%) of cholesterol participating in atherosclerosis, re-questioning the interest of statins in this context. However, awareness is strongly suggested about industrial hydrogenation and subsequently possible excessive consumption of deleterious TFAs.
2.1K
28 Dec 2020
Topic Review
Trans-Endothelial Fatty Acid Transport and Cardiac Metabolism/Contractile
The heart is a metabolic omnivore that combusts a considerable amount of energy substrates, mainly long-chain fatty acids (FAs) and others such as glucose, lactate, ketone bodies, and amino acids. There is emerging evidence that muscle-type continuous capillaries comprise the rate-limiting barrier that regulates FA uptake into cardiomyocytes. The transport of FAs across the capillary endothelium is composed of three major steps—the lipolysis of triglyceride on the luminal side of the endothelium, FA uptake by the plasma membrane, and intracellular FA transport by cytosolic proteins. In the heart, impaired trans-endothelial FA (TEFA) transport causes reduced FA uptake, with a compensatory increase in glucose use. In most cases, mice with reduced FA uptake exhibit preserved cardiac function under unstressed conditions. When the workload is increased, however, the total energy supply relative to its demand (estimated with pool size in the tricarboxylic acid (TCA) cycle) is significantly diminished, resulting in contractile dysfunction. The supplementation of alternative fuels, such as medium-chain FAs and ketone bodies, at least partially restores contractile dysfunction, indicating that energy insufficiency due to reduced FA supply is the predominant cause of cardiac dysfunction.
445
20 Jan 2022
Page
of
1815
Featured Entry Collections
>>
Featured Books
>>
Encyclopedia of Social Sciences
Chief Editor:
Michael McAleer
Encyclopedia of COVID-19
Chief Editor:
Stephen Bustin
Encyclopedia of Fungi
Chief Editor:
Luis V. Lopez-Llorca
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Chief Editor:
Sandro Serpa
Entry
Video
Image
Journal
Book
News
About
Log in/Sign up
New Entry
New Video
New Images
About
Terms and Conditions
Privacy Policy
Advisory Board
Contact
Partner
ScholarVision Creations
Feedback
Top
Feedback
×
Help Center
Browse our user manual, common Q&A, author guidelines, etc.
Rate your experience
Let us know your experience and what we could improve.
Report an error
Is something wrong? Please let us know!
Other feedback
Other feedback you would like to report.
×
Did you find what you were looking for?
Love
Like
Neutral
Dislike
Hate
0
/500
Email
Do you agree to share your valuable feedback publicly on
Encyclopedia
’s homepage?
Yes, I agree. Encyclopedia can post it.
No, I do not agree. I would not like to post my testimonial.
Webpage
Upload a screenshot
(Max file size 2MB)
Submit
Back
Close
×