Chimera (EST)
Encyclopedia
In genetics
, a chimera is a single cDNA sequence originating from two transcripts
. It is usually considered to be a contaminant in transcript and expressed sequence tag
databases. It is estimated that approximately 1% of all transcripts in the National Center for Biotechnology Information
's Unigene database contain a "chimeric sequence".
Methods have been devised to detect them, such as the Ribosomal Database Project's CHECK_CHIMERA program. However, in protein engineering
, "chimeragenesis (forming chimeras between proteins that are encoded by homologous cDNAs)" is one of the "two major techniques used to manipulate cDNA sequences".
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
, a chimera is a single cDNA sequence originating from two transcripts
Transcription (genetics)
Transcription is the process of creating a complementary RNA copy of a sequence of DNA. Both RNA and DNA are nucleic acids, which use base pairs of nucleotides as a complementary language that can be converted back and forth from DNA to RNA by the action of the correct enzymes...
. It is usually considered to be a contaminant in transcript and expressed sequence tag
Expressed sequence tag
An expressed sequence tag or EST is a short sub-sequence of a cDNA sequence. They may be used to identify gene transcripts, and are instrumental in gene discovery and gene sequence determination. The identification of ESTs has proceeded rapidly, with approximately 65.9 million ESTs now available in...
databases. It is estimated that approximately 1% of all transcripts in the National Center for Biotechnology Information
National Center for Biotechnology Information
The National Center for Biotechnology Information is part of the United States National Library of Medicine , a branch of the National Institutes of Health. The NCBI is located in Bethesda, Maryland and was founded in 1988 through legislation sponsored by Senator Claude Pepper...
's Unigene database contain a "chimeric sequence".
Methods have been devised to detect them, such as the Ribosomal Database Project's CHECK_CHIMERA program. However, in protein engineering
Protein engineering
Protein engineering is the process of developing useful or valuable proteins. It is a young discipline, with much research taking place into the understanding of protein folding and recognition for protein design principles....
, "chimeragenesis (forming chimeras between proteins that are encoded by homologous cDNAs)" is one of the "two major techniques used to manipulate cDNA sequences".
Examples
- "The first mRNA transcript isolated for..." the human gene C2orf3C2orf3GC-rich sequence DNA-binding factor is a protein that in humans is encoded by the C2orf3 gene.-Further reading:...
"...was part of an artificial chimera..." - CYP2C17 was thought to be a human gene, but "...is now considered an artefact based on a chimera of CYP2C18CYP2C18Cytochrome P450 2C18 is a protein that in humans is encoded by the CYP2C18 gene.-Further reading:...
and CYP2C19." - Researchers have created receptor chimeras in their studies of Oncostatin MOncostatin MOncostatin M, also known as OSM, is a protein that in humans is encoded by the OSM gene.OSM is a pleiotropic cytokine that belongs to the interleukin 6 group of cytokines. Of these cytokines it most closely resembles leukemia inhibitory factor in both structure and function...
.