Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Horizontal Gene Transfer
Document related concepts
Non-coding DNA wikipedia , lookup
Epigenetics of diabetes Type 2 wikipedia , lookup
Genomic library wikipedia , lookup
Transposable element wikipedia , lookup
Point mutation wikipedia , lookup
Genomic imprinting wikipedia , lookup
Biology and consumer behaviour wikipedia , lookup
Pathogenomics wikipedia , lookup
Gene therapy of the human retina wikipedia , lookup
Epigenetics of human development wikipedia , lookup
Gene nomenclature wikipedia , lookup
Gene desert wikipedia , lookup
Public health genomics wikipedia , lookup
Nutriepigenomics wikipedia , lookup
Minimal genome wikipedia , lookup
Gene therapy wikipedia , lookup
Koinophilia wikipedia , lookup
Gene expression programming wikipedia , lookup
Gene expression profiling wikipedia , lookup
Helitron (biology) wikipedia , lookup
Therapeutic gene modulation wikipedia , lookup
Genome editing wikipedia , lookup
Genetic engineering wikipedia , lookup
Genome (book) wikipedia , lookup
Genome evolution wikipedia , lookup
Site-specific recombinase technology wikipedia , lookup
Vectors in gene therapy wikipedia , lookup
History of genetic engineering wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
Transcript
Section 26.5: Horizontal Gene Transfer By Monica Macaro Learning Objectives Explain why horizontal gene transfer can complicate evolutionary hypothesis Explain why the "Tree of Life" is being replaced by the "Web of Life" Horizontal Gene Transfer Process in which an organism incorporates genetic material from another organism without being its offspring Common in bacteria and archaea, rare in eukaryotic cells Genetic information transferred via conjugation, transduction, and transformation Conjugation Transduction Transformation Horizontal Gene Transfer in Eukaryotes Not well understood Hard to detect Frequency and importance in multicellular eukaryotes hard to evaluate Rare due to sexual reproduction and multicellularity More common in certain unicellular eukaryotes (e.g protists) HGT genes only transferred to offspring in multicellular eukaryotes if recipient was a gamete/germ cell Eukaryote may ingest bacterial cell via endocytosis and incorporate a bacterial gene Bacterial gene may escape degradation Gene incorporated into genome via nonhomologous recombination Genes may be transferred via viruses Viral DNA incorporated into recipient's DNA About 8% of human genome originates from viruses Horizontal Gene Transfer in Eukaryote Horizontal Gene Transfer and Evolution Evolutionary hypothesis focuses on vertical evolution (changes in species due to descent from common ancestor) Genes can be transferred between species via HGT New genes may benefit/hinder organism’s chance for survival May foster evolutionary change HGT may have been prevalent during life’s early stages Common ancestor may have been a community of cell lineage evolving as a whole rather than a single cell lineage Muddles concept of monophyletic groups “Web of Life” instead of “Tree of Life” HGT indicated by horizontal connections The Web of Life
