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| | Sloan-Kettering - Homologous Recombination as a Safeguard Against Tumorigenesis |
 | | They exhibit no significant homology with each other, and there are no clear homologs identified in easily manipulated model organisms, such as yeast. | | | The mouse homologs of BRCA1 and BRCA2 (Brca1 and Brca2) share 58 percent and 59 percent identity with their human counterparts, respectively. | | | Direct Evidence for a Role for BRCA1 in Homologous Recombination |
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http://www.mskcc.org/mskcc/html/10571.cfm
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| | Evolutionary Genetics |
| | Structures that are functionless in a species but homologous to a functioning structure in other species are particularly difficult to explain except under the theory of common descent. | | | It is also hard to make sense of the fact that homologous structures can be inefficient or even useless. | | | Nevertheless, if every organism were created independently, it is unclear why there would be so many homologies among certain organisms, while so few among others. |
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http://www.zoology.ubc.ca/~bio336/Bio336/Lectures/Lecture5/Overheads.html
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| | Curious Minds - Articles - Biology & Life - Evolution |
| | Vertebrate limbs are a common example of such homologous structures. | | | A vestigial organ or structure may exist with little or no purpose in one organism, though they have a clear purpose in others. | | | Phylogeny, the study of the ancestry of species, has revealed that structures with similar internal organization may perform divergent functions. |
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http://www.curiousminds.co.uk/Evolution
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| | Learning Skills Program - The Principles Of Classification |
| | Homologous organs are organs which show the same basic structure, the same general relationship to other organs, and the same pattern of very early growth. | | | Furthermore, all these appendages are found in the same part of the body and develop in similar ways. | | | It is based on the principle of homology. |
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http://www.coun.uvic.ca/learn/program/hndouts/class1.html
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| | Evolution and Systematics, p. 2 |
| | Characters change from one state to another through the process of evolution. | | | Suppose we tried to define human beings by the possession of hair. | | | Homoplastic characters can distort patterns of relationship indicated by homologous characters because they are often in conflict with them. |
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http://www.ucmp.berkeley.edu/education/events/carlson2.html
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| | Homologous Recombination |
| | This may be thought of as homologous recombination at non-homologous positions. | | | Understanding has been approached with each the genetic, morphological and molecular chromosomes. | | | Homologous (or general) recombination is at the heart of genetics. |
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http://opbs.okstate.edu/~melcher/MG/MGW3/MG35.html
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| | Homolgous Recombination & Knockout Mouse |
| | When an investigator wants to replace one allele with an engineered construct but not affect any other locus in the genome, then the method of choice is homologous recombination. | | | Mouse is good mammalian system but homologous recombination does not work as efficeintly in human cells. | | | The mechanism that performs this alignment is poorly understood but it does work better in some species than others. |
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http://www.bio.davidson.edu/courses/genomics/method/homolrecomb.html
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| | homologous - definition from Biology-Online.org |
| | An example of this is the pendactyl limb, which can be found in many organisms, that have all evolved from one common ancestor. | | | Corresponding or similar in position or structure or function or characteristics; especially derived from an organism of the same species; "a homologous tissue graft". | | | Corresponding in structure, position, origin, etc., such as the feathers of a bird and the scales of a fish, the antigen and its specific antibody, the allelic chromosomes. |
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http://www.biology-online.org/dictionary/homologous
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| | Homology: A Concept in Crisis. Origins & Design 18:2. Wells, Jonathan |
| | The neural tube, embryonic precursor of the spinal cord, is regarded as homologous throughout the chordates, yet in some its formation depends on induction by the underlying notochord while in others it does not. | | | Homology in some cases may or may not be due to inheritance from a common ancestor, but it is definitely not due to similarity of genes or similarity of developmental pathways. | | | Not only are non-homologous structures produced by organisms with supposedly homologous genes, but organisms with different genes can also produce similar structures. |
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http://www.arn.org/docs/odesign/od182/hobi182.htm
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| | Gene Targeting via Homologous and Nonhomologous DNA Transformation |
| | Are the non-homologous end-joining and homologous recombination pathways in competition and what genes are important for each pathway? | | | To address this question the genetic components of the end-joining pathway or homologous recombination pathways are being deleted and the strains are being tested for their effect on gene targeting | | | This low frequency of DNA integration by homologous recombination makes it exceeding difficult to carry out "reverse genetics" whereby mutations can be corrected or new mutations can be specifically introduced. |
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http://www.bio.brandeis.edu/haberlab/jehsite/gntarget.html
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| | Homologous Structures |
| | Here we see considerable similarity in the basic skeletal organization of forearms of several types of vertebrates. | | | This Figure Illustrates Similarities Homologous Bone Arrangements in Several Vertebrates |
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http://tidepool.st.usm.edu/crswr/homologousstructs.html
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| | homologous : Definition |
| | The structures or traits in their current forms may not necessarily perform the same functions in each organism, nor perform the functions it did in the common ancestor. | | | In Biology homologous may refer to two anatomical structures or behavioral traits within different organisms which originated from a structure or trait of their common ancestral organism. | | | An example: the wing of a bat, the fin of a whale and the arm of a man are homologous structures. |
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http://www.everythingbio.com/glos/definition.php?ID=3385
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| | [No title] |
| | This is essentially a log during list processing, including all relationships encountered during processing. | | | HOMOLOGS A list of homologous chains is in file 'homologs.25', with percent identity, alignment length and Abagyan-distance given in column 3,4 and 5, resp. | | | If you feel this is too generous, let me know. |
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http://bioinfo.tg.fh-giessen.de/pdbselect/README
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| | Homology (biology) - Wikipedia, the free encyclopedia |
| | Asking whether two sequences are homologous is a yes-or-no question—there is no such condition as "degrees of homology." Sequence regions that are homologous may also be called conserved. | | | A pair of sequences that are orthologous to each other are called orthologs (see Orthologue), a pair that are paralogous are called paralogs. | | | This is a common problem in bioinformatics: when the genome of different species have been sequenced and homologous genes have been found, one can not immediately conclude that these genes have the same or similar function, as they could be paralogs whose function has diverged. |
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http://en.wikipedia.org/wiki/Homology_(biology)
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| | Evolution |
| | The vestigial tailbone in humans is homologous to the functional tail of other primates. | | | Thus vestigial structures can be viewed as evidence for evolution: organisms having vestigial structures probably share a common ancestry with organisms in with organisms in which the homologous structure is functional. | | | Structures that are embryologically similar, but have different functions, are called homologous structures. |
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http://bioweb.cs.earlham.edu/9-12/evolution/HTML/live.html
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| | CB811: Homologous structures and genes |
| | But although such cases are not explained, that does not mean they are unexplainable. | | | For example, some organs considered homologous arise from different layers of embryological tissues. | | | Thus homologous organs arising from different areas may result simply from mutations in where signalling proteins are expressed. |
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http://www.talkorigins.org/indexcc/CB/CB811.html
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| | Homologous competitive binding curves |
| | The equation for specific binding is derived in Theory of homologous competition binding. | | | Homologous competition experiments only lead to useful results when the concentration of hot ligand is less than half the IC If | | | With some systems it is possible to determine K |
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http://www.graphpad.com/curvefit/homologous_.htm
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| | EPA - Endocrine Homologous Models of Cognitive Development: Effects of Hypothyroidism |
| | Homologous Models of Cognitive Development: Effects of Hypothyroidism | | | > Table2.EPA > Homologous Models of Cognitive Development: Effects of Hypothyroidism | | | Description: This project is designed to help address a high-priority research topic, endocrinedisruptors (Strategic Plan for ORD, U.S. EPA, May 1996, p. |
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http://www.epa.gov/endocrine/inventory/NTD-STAN.html
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| | Homologous Shoes? |
| | FIRST: I start by introducing the basic concepts of Homology and Homologous Pairs. | | | They are very good at memorizing the phrase "Homologous Pairs", but they find it extremely difficult to visualize what they are and understand Homology's significance. | | | This outburst led to the "concept demonstration" that I do every year to help illustrate the concept of homology. |
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http://www.accessexcellence.org/AE/AEC/AEF/1994/carroll_homologous.html
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| | [8] Homologous Recombination |
| | During meiosis, two homologous pairs of sister chromatids align side by side. | | | (b) The two homologs are connected at a certain point called chiasma. | | | The DNA crossover is very likely to occur. |
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http://www.web-books.com/MoBio/Free/Ch8D1.htm
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| | Center News |
| | Segmental maps were used to analyze homologous relationships across the vertebrates, and fine-scale DNA comparisons were used to identify slowly evolving regions. | | | The analysis included comparisons between human chromosome 16 and homologous chimpanzee, dog, mouse, rat, chicken, and fish (Fugu) sequences. | | | For example, a 450-kb inversion was found to exist between two haplotypes of one of the most extensively duplicated regions, containing genes for a subunit of eukaryotic translation initiation factor 3 (EIF3S8), sulphotransferase 1A, and Batten disease. |
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http://www-shgc.stanford.edu/news
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| | HOVERGEN |
| | Sequences and related information have been structured in an ACNUC database. | | | Homologous proteins are classified into families and multiple alignments and phylogenetic trees are computed for each family. | | | HOVERGEN is a database of homologous vertebrate genes, structured under ACNUC sequence database management system. |
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http://pbil.univ-lyon1.fr/databases/hovergen.html
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| | NodeWorks - Encyclopedia: Homologous series |
| | Alkanes (paraffins), alkenes (olefins), and alkynes (acetylenes) form such series in which members differ in mass by 14, 12, and 10 atomic mass units respectively. | | | For example, the alkane homologous series begins with methane (CH4), ethane (C2H6), propane (C3H8), butane (C4H10), and pentane (C5H12), each member differing from the previous one by a CH2 group (or 14 atomic mass units). | | | For example, all the members of the alkane series differ by a relative atomic mass of 14. |
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http://pedia.nodeworks.com/H/HO/HOM/Homologous_series
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| | DNA Repair |
| | Recombination between homologous chromosomes in meiosis I also involves the formation of DSBs and their repair. | | | This requires searching around in the nucleus for the homolog — a task sufficiently uncertain that G | | | Cells also use the MMR system to enhance the fidelity of recombination; i.e., assure that only homologous regions of two DNA molecules pair up to crossover and recombine segments (e.g., in meiosis). |
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http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/D/DNArepair.html
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| | Profile |
| | Smith GR, Homologous recombination in E. coli: multiple pathways for multiple reasons, Cell, 58(5), 807-9, September 1989 | | | Ennis DG, Amundsen SK, Smith GR, Genetic functions promoting homologous recombination in Escherichia coli: a study of inversions in phage lambda, Genetics, 115(1), 11-24, January 1987 | | | Smith GR, Homologous recombination near and far from DNA breaks: alternative roles and contrasting views, Annual Review of Genetics, 35, 243-74, 2001 |
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http://myprofile.cos.com/smithabc102
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| | Homologous Recombination |
| | Homologous recombination requires the a nick or break in dsDNA, invasion of a homologous dsDNA molecule by a ssDNA end, pairing of homologous sequences, branch migration to form a Holliday junction, and isomerization of the flanking sequences. | | | Early models proposed that only a limited amount of DNA synthesis is required for recombination. |
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http://www.sci.sdsu.edu/~smaloy/MicrobialGenetics/topics/genetic-analysis/recombination/rec-molecular.html
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| | CPOS - Center for Polymers and Organic Solids |
| | Heeger, AJ (Reprint); Wudl, F; Sariciftci, NS; Janssen, RAJ; Martin, N. Photoinduced Electron Transfer Between Conjugated Polymers And A Homologous Series Of TCNQ Derivatives. |
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http://www.cpos.ucsb.edu/publications.html
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