Intron: right|thumbnail|270px|Representation of intron and [[exons within a simple gene containing a single intron.]]Symmetry element: A symmetry element is a point of reference about which symmetry operations can take place. In particular, symmetry elements can be centers of inversion, axes of rotation and mirror planes.Alternative splicing: Alternative splicing is a regulated process during gene expression that results in a single gene coding for multiple proteins. In this process, particular exons of a gene may be included within or excluded from the final, processed messenger RNA (mRNA) produced from that gene.Coles PhillipsU11 spliceosomal RNAMolecular evolution: Molecular evolution is a change in the sequence composition of cellular molecules such as DNA, RNA, and proteins across generations. The field of molecular evolution uses principles of evolutionary biology and population genetics to explain patterns in these changes.Protein primary structure: The primary structure of a peptide or protein is the linear sequence of its amino acid structural units, and partly comprises its overall biomolecular structure. By convention, the primary structure of a protein is reported starting from the amino-terminal (N) end to the carboxyl-terminal (C) end.Branching order of bacterial phyla (Gupta, 2001): There are several models of the Branching order of bacterial phyla, one of these was proposed in 2001 by Gupta based on conserved indels or protein, termed "protein signatures", an alternative approach to molecular phylogeny. Some problematic exceptions and conflicts are present to these conserved indels, however, they are in agreement with several groupings of classes and phyla.Ligation-independent cloning: Ligation-independent cloning (LIC) is a form of molecular cloning that is able to be performed without the use of restriction endonucleases or DNA ligase. This allows genes that have restriction sites to be cloned without worry of chopping up the insert.Nucleic acid structure: Nucleic acid structure refers to the structure of nucleic acids such as DNA and RNA. Chemically speaking, DNA and RNA are very similar.CS-BLASTMature messenger RNA: Mature messenger RNA, often abbreviated as mature mRNA is a eukaryotic RNA transcript that has been spliced and processed and is ready for translation in the course of protein synthesis. Unlike the eukaryotic RNA immediately after transcription known as precursor messenger RNA, it consists exclusively of exons, with all introns removed.U6 spliceosomal RNADNA sequencer: A DNA sequencer is a scientific instrument used to automate the DNA sequencing process. Given a sample of DNA, a DNA sequencer is used to determine the order of the four bases: G (guanine), C (cytosine), A (adenine) and T (thymine).Hairpin ribozymeGroup III intron: Group III intron is a class of introns found in mRNA genes of chloroplasts in euglenid protists. They have a conventional group II-type dVI with a bulged adenosine, a streamlined dI, no dII-dV, and a relaxed splice site consensus.Eukaryotic transcription: Eukaryotic transcription is the elaborate process that eukaryotic cells use to copy genetic information stored in DNA into units of RNA replica. Gene transcription occurs in both eukaryotic and prokaryotic cells.DNA condensation: DNA condensation refers to the process of compacting DNA molecules in vitro or in vivo. Mechanistic details of DNA packing are essential for its functioning in the process of gene regulation in living systems.Open reading frame: In molecular genetics, an open reading frame (ORF) is the part of a reading frame that has the potential to code for a protein or peptide. An ORF is a continuous stretch of codons that do not contain a stop codon (usually UAA, UAG or UGA).Trans-splicing: Trans-splicing is a special form of RNA processing in eukaryotes where exons from two different primary RNA transcripts are joined end to end and ligated.Chromosome regionsList of sequenced eukaryotic genomesThermal cyclerHaematococcus pluvialis: Haematococcus pluvialis is a freshwater species of Chlorophyta from the family Haematococcaceae. This species is well known for its high content of the strong antioxidant astaxanthin, which is important in aquaculture, and cosmetics.Nucleomorph: Nucleomorphs are small, vestigial eukaryotic nuclei found between the inner and outer pairs of membranes in certain plastids. They are thought to be vestiges of primitive red and green algal nuclei that engulfed a prokaryote (plastid).YjdF RNA motifLasiodiplodia: Lasiodiplodia is a genus of fungi in the family Botryosphaeriaceae. There are 21 species.Ty5 retrotransposon: The Ty5 is a type of retrotransposon native to the Saccharomyces cerevisiae organism.MT-RNR2: Mitochondrially encoded 16S RNA (often abbreviated as 16S) is a mitochondrial ribosomal RNA (rRNA) that in humans is encoded by the MT-RNR2 gene. The MT-RNR2 gene also encodes the Humanin polypeptide that has been the target of Alzheimer's disease research.Vg1 ribozyme: The Vg1 ribozyme is a manganese dependent RNA enzyme or ribozyme which is the smallest ribozyme to be identified. It was identified in the 3' UTR of Xenopus Vg1 mRNA transcripts and mouse beta-actin mRNA.GC box: In molecular biology, a GC box is a distinct pattern of nucleotides found in the promoter region of some eukaryotic genes upstream of the TATA box and approximately 110 bases upstream from the transcription initiation site. It has a consensus sequence GGGCGG which is position dependent and orientation independent.Silent mutation: Silent mutations are mutations in DNA that do not significantly alter the phenotype of the organism in which they occur. Silent mutations can occur in non-coding regions (outside of genes or within introns), or they may occur within exons.Synanceia: Synanceia is a genus of fish of the family Synanceiidae, the stonefishes, whose members are venomous, dangerous, and even fatal to humans. It is one of the most venomous fish currently known in the world.Naegleria: Naegleria is a genus of protozoa. The genus was named after French zoologist Mathieu Naegler.ParaHox: The ParaHox gene cluster is an array of homeobox genes (involved in morphogenesis, the regulation of patterns of anatomical development) from the Gsx, Xlox (Pdx) and Cdx gene families.Restriction fragment: A restriction fragment is a DNA fragment resulting from the cutting of a DNA strand by a restriction enzyme (restriction endonucleases), a process called restriction. Each restriction enzyme is highly specific, recognising a particular short DNA sequence, or restriction site, and cutting both DNA strands at specific points within this site.Intergenic region: An Intergenic region (IGR) is a stretch of DNA sequences located between genes. Intergenic regions are a subset of Noncoding DNA.Direct repeat: Direct repeats are a type of genetic sequence that consists of two or more repeats of a specific sequence.Haplogroup L0 (mtDNA)Composite transposon: A composite transposon is similar in function to simple transposons and Insertion Sequence (IS) elements in that it has protein coding DNA segments flanked by inverted, repeated sequences that can be recognized by transposase enzymes. A composite transposon, however, is flanked by two separate IS elements which may or may not be exact replicas.Calkinsia: Calkinsia is a monotypic genus of alga comprising the single species Calkinsia aureus. It lives in low-oxygen seafloor environments.Pyrococcus C/D box small nucleolar RNALeucoplastCodon Adaptation Index: The Codon Adaptation Index (CAI) is the most widespread technique for analyzing Codon usage bias. As opposed to other measures of codon usage bias, such as the 'effective number of codons' (Nc), which measure deviation from a uniform bias (null hypothesis), CAI measures the deviation of a given protein coding gene sequence with respect to a reference set of genes.Marine fungi: Marine fungi are species of fungi that live in marine or estuarine environments. They are not a taxonomic group but share a common habitat.Zuotin: Z-DNA binding protein 1, also known as Zuotin, is a Saccharomyces cerevisiae yeast gene.RNA-binding protein database: The RNA-binding Proteins Database (RBPDB) is a biological database of RNA-binding protein specificities that includes experimental observations of RNA-binding sites. The experimental results included are both in vitro and in vivo from primary literature.Excision repair cross-complementing: Excision repair cross-complementing (ERCC) is a set of proteins which are involved in DNA repair.PerrottetineneIndy (gene): Indy, short for I'm not dead yet, is a gene of the model organism, the fruit fly Drosophila melanogaster. Mutant versions of this gene have doubled the average life span of fruit flies in at least one set of experiments, but this result has been subject to controversy.Sequence clustering: In bioinformatics, sequence clustering algorithms attempt to group biological sequences that are somehow related. The sequences can be either of genomic, "transcriptomic" (ESTs) or protein origin.GAI (Arabidopsis thaliana gene)Protein splicing: Protein splicing is an intramolecular reaction of a particular protein in which an internal protein segment (called an intein) is removed from a precursor protein with a ligation of C-terminal and N-terminal external proteins (called exteins) on both sides. The splicing junction of the precursor protein is mainly a cysteine or a serine, which are amino acids containing a nucleophilic side chain.Puccinia striiformis var. striiformis: Puccinia striiformis var. striiformis is a plant pathogen.RMF RNA motif: The rmf RNA motif is a conserved RNA structure that was originally detected using bioinformatics. rmf RNAs are consistently foundwithin species classified into the genus Pseudomonas, and is located potentially in the 5' untranslated regions (5' UTRs) of rmf genes.PSI Protein Classifier: PSI Protein Classifier is a program generalizing the results of both successive and independent iterations of the PSI-BLAST program. PSI Protein Classifier determines belonging of the found by PSI-BLAST proteins to the known families.Thermoproteales: In taxonomy, the Thermoproteales are an order of the Thermoprotei.See the NCBI webpage on Thermoproteales.NADH-QLibrary (biology): In molecular biology, a library is a collection of DNA fragments that is stored and propagated in a population of micro-organisms through the process of molecular cloning. There are different types of DNA libraries, including cDNA libraries (formed from reverse-transcribed RNA), genomic libraries (formed from genomic DNA) and randomized mutant libraries (formed by de novo gene synthesis where alternative nucleotides or codons are incorporated).Genetic variation: right|thumb