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SNRPN Upstream Reading Frame Protein
SNRPN upstream reading frame protein is a protein that in humans is encoded by the ''SNURF'' gene. Function This gene encodes a highly basic protein localized to the nucleus. The evolutionarily constrained open reading frame is found on a bicistronic transcript which has a downstream ORF encoding the small nuclear ribonucleoprotein polypeptide N. The upstream coding region utilizes the first three exons of the transcript, a region that has been identified as an imprinting center. Multiple transcription initiation sites have been identified and extensive alternative splicing occurs in the 5' untranslated region but the full-length nature of these transcripts has not been determined. An alternate exon has been identified that substitutes for exon 4 and leads to a truncated, monocistronic transcript. Alternative splicing or deletion caused by a translocation event in the 5' untranslated region or coding region of this gene leads to Angelman syndrome Angelman syndrome (AS ... [...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] |
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: protein-coding genes and non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Open Reading Frame
In molecular biology, reading frames are defined as spans of DNA sequence between the start and stop codons. Usually, this is considered within a studied region of a prokaryotic DNA sequence, where only one of the six possible reading frames will be "open" (the "reading", however, refers to the RNA produced by transcription of the DNA and its subsequent interaction with the ribosome in translation). Such an open reading frame (ORF) may contain a start codon (usually AUG in terms of RNA) and by definition cannot extend beyond a stop codon (usually UAA, UAG or UGA in RNA). That start codon (not necessarily the first) indicates where translation may start. The transcription termination site is located after the ORF, beyond the translation stop codon. If transcription were to cease before the stop codon, an incomplete protein would be made during translation. In eukaryotic genes with multiple exons, introns are removed and exons are then joined together after transcription to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small Nuclear Ribonucleoprotein Polypeptide N
Small nuclear ribonucleoprotein-associated protein N is a protein that in humans is encoded by the ''SNRPN'' gene. The protein encoded by this gene is one polypeptide of a small nuclear ribonucleoprotein complex and belongs to the snRNP SMB/SMN family. The protein plays a role in pre-mRNA processing, possibly tissue-specific alternative splicing events. Although individual snRNPs are believed to recognize specific nucleic acid sequences through RNA-RNA base pairing, the specific role of this family member is unknown. The protein arises from a bicistronic transcript that also encodes a protein identified as the SNRPN upstream reading frame (SNURF). Multiple transcription initiation sites have been identified and extensive alternative splicing occurs in the 5' untranslated region. Additional splice variants have been described but sequences for the complete transcripts have not been determined. The 5' UTR of this gene has been identified as an imprinting center. Alternative splicing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exon
An exon is any part of a gene that will form a part of the final mature RNA produced by that gene after introns have been removed by RNA splicing. The term ''exon'' refers to both the DNA sequence within a gene and to the corresponding sequence in RNA transcripts. In RNA splicing, introns are removed and exons are covalently joined to one another as part of generating the mature RNA. Just as the entire set of genes for a species constitutes the genome, the entire set of exons constitutes the exome. History The term ''exon'' is a shortening of the phrase ''expressed region'' and was coined by American biochemist Walter Gilbert in 1978: "The notion of the cistron... must be replaced by that of a transcription unit containing regions which will be lost from the mature messengerwhich I suggest we call introns (for intragenic regions)alternating with regions which will be expressedexons." This definition was originally made for protein-coding transcripts that are spliced before b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription Start Site
Transcription is the process of copying a segment of DNA into RNA for the purpose of gene expression. Some segments of DNA are transcribed into RNA molecules that can encode proteins, called messenger RNA (mRNA). Other segments of DNA are transcribed into RNA molecules called non-coding RNAs (ncRNAs). 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. In virology, the term transcription is used when referring to mRNA synthesis from a viral RNA molecule. The genome of many RNA viruses is composed of negative-sense RNA which acts as a template for positive sense viral messenger RNA - a necessary step in the synthesis of viral proteins needed for viral replication. This process is catalyzed by a viral RNA dependent RNA polymerase. Background A DNA transcription unit encoding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocistronic
A cistron is a region of DNA that is conceptually equivalent to some definitions of a gene, such that the terms are synonymous from certain viewpoints, especially with regard to the molecular gene as contrasted with the Mendelian gene. The question of which scope of a subset of DNA (that is, how large a segment of DNA) constitutes a unit of selection is the question that governs whether cistrons are the same thing as genes. The word ''cistron'' is used to emphasize that molecular genes exhibit a specific behavior in a complementation test (cis-trans test); distinct positions (or loci) within a genome are cistronic. History The words ''cistron'' and ''gene'' were coined before the advancing state of biology made it clear to many people that the concepts they refer to, at least in some senses of the word ''gene'', are either equivalent or nearly so. The same historical naming practices are responsible for many of the synonyms in the life sciences. The term ''cistron'' was co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome Translocation
In genetics, chromosome translocation is a phenomenon that results in unusual rearrangement of chromosomes. This includes "balanced" and "unbalanced" translocation, with three main types: "reciprocal", "nonreciprocal" and "Robertsonian" translocation. Reciprocal translocation is a chromosome abnormality caused by exchange of parts between non-homologous chromosomes. Two detached fragments of two different chromosomes are switched. Robertsonian translocation occurs when two non-homologous chromosomes get attached, meaning that given two healthy pairs of chromosomes, one of each pair "sticks" and blends together homogeneously. Each type of chromosomal translocation can result in disorders for growth, function and the development of an individuals body, often resulting from a change in their genome. A gene fusion may be created when the translocation joins two otherwise-separated genes. It is detected on cytogenetics or a karyotype of affected cells. Translocations can be balanced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Untranslated Region
In molecular genetics, an untranslated region (or UTR) refers to either of two sections, one on each side of a coding sequence on a strand of mRNA. If it is found on the Directionality (molecular biology), 5' side, it is called the Five prime untranslated region, 5' UTR (or leader sequence), or if it is found on the Directionality (molecular biology), 3' side, it is called the Three prime untranslated region, 3' UTR (or trailer sequence). mRNA is RNA that carries information from DNA to the ribosome, the site of protein synthesis (Translation (biology), translation) within a cell. The mRNA is initially Transcription (genetics), transcribed from the corresponding DNA sequence and then translated into protein. However, several regions of the mRNA are usually not translated into protein, including the 5' and 3' UTRs. Although they are called untranslated regions, and do not form the Coding region, protein-coding region of the gene, Upstream open reading frame, uORFs located withi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angelman Syndrome
Angelman syndrome (AS) is a genetic disorder that affects approximately 1 in 15,000 individuals. AS impairs the function of the nervous system, producing symptoms, such as severe intellectual disability, developmental disability, limited to no functional speech, balance and movement problems, seizures, hyperactivity, and sleep problems. Physical symptoms include a small head and a specific facial appearance. Additionally, those affected usually have a happy personality and have a particular interest in water. Angelman syndrome involves genes that have also been linked to 1–2% of autism spectrum disorder cases. Epidemiology Though the prevalence of Angelman syndrome is not precisely known, there are some estimates. The best data available are from studies of school age children, ages 6–13 years, living in Sweden and from Denmark where the diagnosis of AS children in medical clinics was compared to an 8-year period of about 45,000 births. The Swedish study showed an AS preva ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
