PSEUDOGENES
What are they, where do they come from and what can we learn from them?
PSEUDOGENESWhat are they, where do they come from and what can we learn from them?
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Creation vs. Evolution:
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ADP: stands for adenosine diphosphate. It is a phosphate sugar nucleotide involved in energy transfer and often works with enzymes. Alu: Alu sequences are highly repetitive sequences found in large numbers (100-500,000) in the human genome, and that are cleaved more than once within each sequence by the Alu endonuclease. The Alu sequences look like DNA copies of mRNA because they have a 3' poly-A tail and flanking repeats. A category of well-known SINEs. DNA damaging-agent: cause mutations in the DNA sequence. Nucleotides are deleted, added or changed. These mutations can lead to cancer if certain genes are damaged. Exon
: Protein coding sequences of a gene that will ultimately show up in the mRNA. Flanking direct repeats: Short DNA sequences present on either side of a transcriptional unit. Gene duplication: A class of DNA rearrangement that generates multiple copies of a gene in the genome. Genetic markers: are known short sequences of DNA or RNA nucleotides that can be used to identify a gene, a particular group of genes, or an individual. Genetic markers can be used in medicine to study genetic aspects of disease. Gene families (genes that are generally inherited as a group) can be identified from markers. Genetic recombination: a normal process that occurs during meiosis (sexual reproduction) when the DNA is replicated (an identical copy of a strand is made). DNA is cleaved and the fragments are rejoined to give new strands. This allows genetic information from maternal and paternal chromosomes to be incorporated into a new genome. The chances that nucleotides from one strand will cross and be on separate DNA strands increases with increasing distance between them. Thus genes that lie close together on the genome are more likely to be inherited together. Heterozygosity: refers to having different alleles (forms) of a particular gene. Homopolymer:
A chain of identical bases: AAAAA…, CCCCC…, GGGGG…, or TTTTT…. Homozygosity: refers to having two identical alleles (forms) of a particular gene. Intron:
Non-coding sequences of genes which are initially transcribed, along with
exons,into RNA but are spliced out by mRNA processing . LINE:
Long interspersed nuclear element. A group of retropseudogenes that occur in the hundreds of thousands in the human genome and which are typically about 7000 bases long. Multiple myeloma: is cancer of the plasma cells of the bone marrow. Ortholog: Genes and/or pseudogenes which is a counterpart to a similar gene and/or pseudogene in another primate. An ortholog is presumed to be a copy of an ancestral gene sequence and is thus related by common phylogenetic descent. PADPRP: Poly(ADP-ribose)polymerase. Phenotype
: Physical observable features of an organisms. Phylogeny: The evolution of an animal or plant type. Related to the construction of an evolutionary tree. Polyadenylation tract: A polyadenylyl moiety bound covalently to the 3’ end of processed mRNA molecules. Polymerase: is an enzyme that catalyzes DNA or RNA transcription. Polymorphisms: are different versions of a gene, due to differences in nucleotides on the DNA. Promoter:
A specific site, upstream of genes, on DNA to which RNA polymerase binds and
initiates transcription. Pseudogene: DNA sequence that resembles a homologue normal gene but seems to have no function. Retropseudogene: A structure created by the reverse transcription of RNA back into the host DNA. Reverse Transcription: Synthesis of a DNA molecule (coding DNA or cDNA) from RNA. Ribose: is a five carbon sugar that is often found associated with RNA nucleotides. Deoxyribose is a five carbon sugar that is associated with DNA nucleotides. SINE: Short interspersed nuclear element. A group of retropseudogenes that occur in the hundreds of thousands in the human genome and each of which is typically about 300 bases long. Template:
A nucleic acid molecule whose sequence is used to synthesize a complementary DNA
(in replication) or RNA (in transcription) strand. Transcription: Synthesis of an RNA molecule from a gene. Vestige: A trace of some part or organ formerly present in the body.
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