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EIF5A
Eukaryotic translation initiation factor 5A-1 is a protein that in humans is encoded by the ''EIF5A'' gene. It is the only known protein to contain the unusual amino acid hypusine 'N''ε-(4-amino-2-hydroxybutyl)-lysine which is synthesized on eIF5A at a specific lysine residue from the polyamine spermidine by two catalytic steps. EF-P is the bacterial homolog of eIF5A, which is modified post-translationally in a similar but distinct way. Both proteins are believed to catalyze peptide bond formation and help resolve ribosomal stalls, making them elongation factors despite the "initiation factor" name originally assigned. Faundes-Banka syndrome Germline deleterious heterozygous ''EIF5A'' variants cause Faundes-Banka syndrome. This rare human disorder is characterized by variable combinations of developmental delay, microcephaly Microcephaly (from Neo-Latin ''microcephalia'', from Ancient Greek μικρός ''mikrós'' "small" and κεφαλή ''kephalé'' "head") is a me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypusine
Hypusine is an uncommon amino acid found in all eukaryotes and in some archaea, but not in bacteria. The only known proteins containing the hypusine residue is eukaryotic translation initiation factor 5A (eIF-5A) and a similar protein found in archaea. In humans, two isoforms of eIF-5A have been described: eIF5A-1 and eIF5A-2. They are encoded by two distinct genes EIF5A and EIF5A2. The protein is involved in protein biosynthesis and promotes the formation of the first peptide bond. The region surrounding the hypusine residue is highly conserved and is essential to the function of eIF5A. Thus, hypusine and eIF-5A appear to be vital for the viability and proliferation of eukaryotic cells. Hypusine is formed in eIF-5A by post-translational modification of one of the lysyl residues. Two reactions and two enzymes are involved: *1. Deoxyhypusine synthase catalyzes the cleavage of the polyamine spermidine and transfer of its 4-aminobutyl moiety to the ε-amino group of one spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EIF5A2
Eukaryotic translation initiation factor 5A-2 is a protein that in humans is encoded by the ''EIF5A2'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei .... References Further reading * * * * * * * * * * * * * * * {{gene-3-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elongation Factor P
EF-P (elongation factor P) is an essential protein that in bacteria stimulates the formation of the first peptide bonds in protein synthesis. Studies show that EF-P prevents ribosomes from stalling during the synthesis of proteins containing consecutive prolines. EF-P binds to a site located between the binding site for the peptidyl tRNA ( P site) and the exiting tRNA ( E site). It spans both ribosomal subunits with its amino-terminal domain positioned adjacent to the aminoacyl acceptor stem and its carboxyl-terminal domain positioned next to the anticodon stem-loop of the P site-bound initiator tRNA. The EF-P protein shape and size is very similar to a tRNA and interacts with the ribosome via the exit “E” site on the 30S subunit and the peptidyl-transferase center (PTC) of the 50S subunit. EF-P is a translation aspect of an unknown function, therefore It probably functions indirectly by altering the affinity of the ribosome for aminoacyl-tRNA, thus increasing their reactivity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Initiation Factor
In molecular biology, initiation factors are proteins that bind to the small subunit of the ribosome during the initiation of Translation (genetics), translation, a part of protein biosynthesis. Initiation factors can interact with repressors to slow down or prevent translation. They have the ability to interact with Activator (genetics), activators to help them start or increase the rate of translation. In bacteria, they are simply called IFs (i.e.., IF1, IF2, & IF3) and in eukaryotes they are known as eIFs (i.e.., eIF1, eIF2, eIF3). Translation initiation is sometimes described as three step process which initiation factors help to carry out. First, the tRNA carrying a methionine amino acid binds to the small subunit of ribosome, then binds to the mRNA, and finally joins together with the large subunit of ribosome. The initiation factors that help with this process each have different roles and structures. Types The initiation factors are divided into three major groups by ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dysmorphic Feature
A dysmorphic feature is an abnormal difference in body structure. It can be an isolated finding in an otherwise normal individual, or it can be related to a congenital disorder, genetic syndrome or birth defect. Dysmorphology is the study of dysmorphic features, their origins and proper nomenclature. One of the key challenges in identifying and describing dysmorphic features is the use and understanding of specific terms between different individuals. Clinical geneticists and pediatricians are usually those most closely involved with the identification and description of dysmorphic features, as most are apparent during childhood. Dysmorphic features can vary from isolated, mild anomalies such as clinodactyly or synophrys to severe congenital anomalies, such as heart defects and holoprosencephaly. In some cases, dysmorphic features are part of a larger clinical picture, sometimes known as a sequence, syndrome or association. Recognizing the patterns of dysmorphic features is an i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrognathism
Micrognathism is a condition where the jaw is undersized. It is also sometimes called mandibular hypoplasia. It is common in infants, but is usually self-corrected during growth, due to the jaws' increasing in size. It may be a cause of abnormal tooth alignment and in severe cases can hamper feeding. It can also, both in adults and children, make intubation difficult, either during anesthesia or in emergency situations. Causes According to the NCBI, the following conditions feature micrognathism: * 11q partial monosomy syndrome * 3-methylglutaconic aciduria, type VIIB * 46,XY sex reversal 4 * 4p partial monosomy syndrome * Achard syndrome * Acrofacial dysostosis Cincinnati type * Acrofacial dysostosis Rodriguez type * Acrofacial dysostosis, Catania type * Acromegaloid facial appearance syndrome * Adams-Oliver syndrome 2 * Agnathia- otocephaly complex * ALG1-congenital disorder of glycosylation * Alveolar capillary dysplasia with pulmonary venous misalignment * Ami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcephaly
Microcephaly (from Neo-Latin ''microcephalia'', from Ancient Greek μικρός ''mikrós'' "small" and κεφαλή ''kephalé'' "head") is a medical condition involving a smaller-than-normal head. Microcephaly may be present at birth or it may develop in the first few years of life. Brain development is often affected; people with this disorder often have an intellectual disability, poor motor function, poor speech, abnormal facial features, seizures and dwarfism. The disorder is caused by a disruption to the genetic processes that form the brain early in pregnancy, though the cause is not identified in most cases. Many genetic syndromes can result in microcephaly, including chromosomal and single-gene conditions, though almost always in combination with other symptoms. Mutations that result solely in microcephaly (primary microcephaly) exist but are less common. External toxins to the embryo, such as alcohol during pregnancy or vertically transmitted infections, can a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deleterious Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication ( translesion synthesis). Mutations may also result from substitution, insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics (phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutation is the ult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germline
In biology and genetics, the germline is the population of a multicellular organism's cells that develop into germ cells. In other words, they are the cells that form gametes ( eggs and sperm), which can come together to form a zygote. They differentiate in the gonads from primordial germ cells into gametogonia, which develop into gametocytes, which develop into the final gametes. This process is known as gametogenesis. Germ cells pass on genetic material through the process of sexual reproduction. This includes fertilization, recombination and meiosis. These processes help to increase genetic diversity in offspring. Certain organisms reproduce asexually via processes such as apomixis, parthenogenesis, autogamy, and cloning. Apomixis and Parthenogenesis both refer to the development of an embryo without fertilization. The former typically occurs in plants seeds, while the latter tends to be seen in nematodes, as well as certain species of reptiles, birds, and fish. Autogamy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Excessive Length Of Ears; Facial Asymmetry (Peterson 260)
Excess may refer to: * Angle excess, in spherical trigonometry * Insurance excess, similar to a deductible * Excess, in chemistry, a reagent that is not the limiting reagent * "Excess", a song by Tricky from the album '' Blowback'' * ''Excess'' (album), an album by Coma See also * Excess-K Offset binary, also referred to as excess-K, excess-''N'', excess-e, excess code or biased representation, is a method for signed number representation where a signed number n is represented by the bit pattern corresponding to the unsigned numbe ..., or offset binary, in computing * XS (other) {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elongation Factors
Elongation may refer to: * Elongation (astronomy) * Elongation (geometry) * Elongation (plasma physics) * Part of transcription of DNA into RNA of all types, including mRNA, tRNA, rRNA, etc. * Part of translation (biology) of mRNA into proteins * Elongated organisms * Elongation (mechanics) In physics and continuum mechanics, deformation is the change in the shape or size of an object. It has dimension of length with SI unit of metre (m). It is quantified as the residual displacement of particles in a non- rigid body, from an con ..., linear deformation See also * {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
