This web page was produced as an assignment for Genetics 564, an undergraduate course at UW-Madison.
What is homology?
Homology is the presence of shared ancestry between different species, via genes or physical traits, by a common ancestor. A common example of homology is that of specific vertebrates (Figure1) which all have the same forelimb bone structure, though today they may look nothing alike on the outside because of evolution (1).
I am looking at homology of the FLNB gene across various species, a process known as gene homology. Gene homology is where the genes of a species are conserved through time by a common ancestor. These genes may not necessarily have the same sequence as they once had, because of variations in the genome by evolution, but should still have a fairly conserved sequence structure to be identified as the same or similar gene. Shown below are species that have homology with the FLNB gene. *Note gene name changes across species. |
What's the homology of FLNB gene?
The FLNB gene homology across various species (Figure 2) resulted in being very conserved in percent identity to the human FLNB gene, and appeared in all vertebrate species. The FLNB gene is more conserved in mammalian species and decreases when it comes to other species such as the zebrafish, a bony fish from the class Actinopterygii (2). Several organisms were unable to be found in relation to the FLNB gene such as the nematode, fruit fly, or plant leading them to not appear to be homologous species, but were found for the FLNB protein. To find homologous species in relation to the FLNB gene the human DNA accession number was obtained using ENTREZ. The human accession number NC_000003.11 was obtained which provided the genetic code to the complete chromosome 3, where the FLNB gene is located at p14.3. Because I didn't find searching for homologous species using the complete chromosome 3 sequence would benefit my research, I discovered the FLNB cDNA accession number, AF043045.1, using GenBank. This FLNB cDNA information was used for all FLNB gene research. I was then able to compare another organism against my human FLNB gene to identify homologs to my gene using BLAST for two sequences. I also used Homologene to find similar homologous organisms in respect to the FLNB gene. A reciprocal BLAST was done to verify the results from homologous species information as well as their percent identification to humans. *PDF of annotated FASTA of homologous species shown below.
Analysis of FLNB gene homology:
The FLNB gene proved to be homologous in several species. The mammalian species were most commonly found, although the zebrafish, an Actinopterygii (2), was able to be identified, as well as the chicken. The FLNB gene showed to be present in several popular model organisms such as the mouse and zebra fish, but was unable to be identified in C. elegans (nematode) or Drosophila (fruit fly). Their absence of the FLNB gene could be because these organisms are invertebrates, where as the FLNB gene is an actin- binding protein commonly involved in the development of cartilage and bone (3). But these species were identified in the FLNB protein homology. This might pose that the FLNB gene either hasn't been discovered yet in commonly studied invertebrate species, like C. elegans, or that something else maybe occurring. Of the homologous species discovered, they proved to be conserved in percent identity when compared to the human FLNB gene.
Homolog DNA Reference Pages:
Human (Homo sapien) - Actin-binding protein
Accession Number: AF043045.1 GI Number: 3282770 FASTA Zebra Fish (Danio rerio) - Filamin B Accession Number: XM_001919485.4 GI Number: 528494953 Max Identical: 73% E- value: 0.0 FASTA Chimp (Pan troglodytes) - Filamin B Accession Number: XM_001173996.2 GI Number: 332817062 Max Identical: 99. 3% E-value: 0.0 FASTA Rhesus Monkey (Macaca mulatta) - Filamin B Accession Number: XM_001097922.2 GI Number: 297285532 Max Identical: 96.3% E-value: 0.0 FASTA Dog (Canis lupus) - Filamin B Accession Number: XM_541829.4 GI Number: 545533306 Max Identical: 91.2% E-value: 0.0 FASTA |
Cattle (Bos Taurus) - Filamin B
Accession Number: XM_005222906.1 GI Number: 529001704 Max Identical: 90.2% E-value: 0.0 FASTA House mouse (Mus musculus) - Filamin B Accession Number: XM_006518049.1 GI Number: 568985490 Max Identical: 87.9% E-value: 0.0 FASTA Norway Rat (Rattus norvegicus) - Filamin B Accession Number: XM_006251780.1 GI Number: 564385703 Max Identical: 87.6% E-value: 0.0 FASTA Chicken (Gallus gallus) - Filamin B Accession Number: NM_001030341.1 GI Number: 71896430 Max Identical: 75.8% E-value: 0.0 FASTA |
FLNB gene homology FASTA.pdf | |
File Size: | 264 kb |
File Type: |
References:
1.) "Wikipedia: Homology (biology)". Web. Feb, 20, 2014. http://en.wikipedia.org/wiki/Homology_(biology)
2.) "Wikipedia: Zebrafish". Web. May, 14, 2014. http://en.wikipedia.org/wiki/Zebrafish
3.)3.) Zhou, X., et. al., (2007). "Filamin B deficiency in mice results in skeletal malformations and impaired microvascular development". PNAS. 104(10), doi: 10.1073/pnas.0608360104
2.) "Wikipedia: Zebrafish". Web. May, 14, 2014. http://en.wikipedia.org/wiki/Zebrafish
3.)3.) Zhou, X., et. al., (2007). "Filamin B deficiency in mice results in skeletal malformations and impaired microvascular development". PNAS. 104(10), doi: 10.1073/pnas.0608360104