Summary: HIF-1 alpha C terminal transactivation domain
Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.
This is the Wikipedia entry entitled "Hypoxia-inducible factors". More...
The Wikipedia text that you see displayed here is a download from Wikipedia. This means that the information we display is a copy of the information from the Wikipedia database. The button next to the article title ("Edit Wikipedia article") takes you to the edit page for the article directly within Wikipedia. You should be aware you are not editing our local copy of this information. Any changes that you make to the Wikipedia article will not be displayed here until we next download the article from Wikipedia. We currently download new content on a nightly basis.
Does Pfam agree with the content of the Wikipedia entry ?
Pfam has chosen to link families to Wikipedia articles. In some case we have created or edited these articles but in many other cases we have not made any direct contribution to the content of the article. The Wikipedia community does monitor edits to try to ensure that (a) the quality of article annotation increases, and (b) vandalism is very quickly dealt with. However, we would like to emphasise that Pfam does not curate the Wikipedia entries and we cannot guarantee the accuracy of the information on the Wikipedia page.
Editing Wikipedia articles
Before you edit for the first time
Wikipedia is a free, online encyclopedia. Although anyone can edit or contribute to an article, Wikipedia has some strong editing guidelines and policies, which promote the Wikipedia standard of style and etiquette. Your edits and contributions are more likely to be accepted (and remain) if they are in accordance with this policy.
You should take a few minutes to view the following pages:
How your contribution will be recorded
Anyone can edit a Wikipedia entry. You can do this either as a new user or you can register with Wikipedia and log on. When you click on the "Edit Wikipedia article" button, your browser will direct you to the edit page for this entry in Wikipedia. If you are a registered user and currently logged in, your changes will be recorded under your Wikipedia user name. However, if you are not a registered user or are not logged on, your changes will be logged under your computer's IP address. This has two main implications. Firstly, as a registered Wikipedia user your edits are more likely seen as valuable contribution (although all edits are open to community scrutiny regardless). Secondly, if you edit under an IP address you may be sharing this IP address with other users. If your IP address has previously been blocked (due to being flagged as a source of 'vandalism') your edits will also be blocked. You can find more information on this and creating a user account at Wikipedia.
If you have problems editing a particular page, contact us at firstname.lastname@example.org and we will try to help.
The community annotation is a new facility of the Pfam web site. If you have problems editing or experience problems with these pages please contact us.
Hypoxia-inducible factors Edit Wikipedia article
|hypoxia-inducible factor 1, alpha subunit|
|Locus||Chr. 14 q21-q24|
|aryl hydrocarbon receptor nuclear translocator|
|Alt. symbols||HIF1B, bHLHe2|
|Locus||Chr. 1 q21|
|endothelial PAS domain protein 1|
|Alt. symbols||HIF2A, MOP2, PASD2, HLF|
|Locus||Chr. 2 p21-p16|
|aryl-hydrocarbon receptor nuclear translocator 2|
|Alt. symbols||HIF2B, KIAA0307, bHLHe1|
|Locus||Chr. 1 q24|
|hypoxia inducible factor 3, alpha subunit|
|Locus||Chr. 19 q13|
Most, if not all, oxygen-breathing species express the highly-conserved transcriptional complex HIF-1, which is a heterodimer composed of an alpha and a beta subunit, the latter being a constitutively-expressed aryl hydrocarbon receptor nuclear translocator (ARNT). HIF-1 belongs to the PER-ARNT-SIM (PAS) subfamily of the basic helix-loop-helix (bHLH) family of transcription factors. The alpha and beta subunit are similar in structure and both contain the following domains:
- N-terminus – a bHLH domain for DNA binding
- central region – Per-ARNT-Sim (PAS) domain which facilitates heterodimerization
- C-terminus – recruits transcriptional coregulatory proteins
The following are members of the human HIF family:
|HIF-1α||HIF1A||hypoxia-inducible factor 1, alpha subunit|
|HIF-1β||ARNT||aryl hydrocarbon receptor nuclear translocator|
|HIF-2α||EPAS1||endothelial PAS domain protein 1|
|HIF-2β||ARNT2||aryl-hydrocarbon receptor nuclear translocator 2|
|HIF-3α||HIF3A||hypoxia inducible factor 3, alpha subunit|
|HIF-3β||ARNTL||aryl-hydrocarbon receptor nuclear translocator 3|
The HIF signaling cascade mediates the effects of hypoxia, the state of low oxygen concentration, on the cell. Hypoxia often keeps cells from differentiating. However, hypoxia promotes the formation of blood vessels, and is important for the formation of a vascular system in embryos, and cancer tumors. The hypoxia in wounds also promotes the migration of keratinocytes and the restoration of the epithelium.
In general, HIFs are vital to development. In mammals, deletion of the HIF-1 genes results in perinatal death. HIF-1 has been shown to be vital to chondrocyte survival, allowing the cells to adapt to low-oxygen conditions within the growth plates of bones. HIF plays a central role in the regulation of human metabolism.
The alpha subunits of HIF are hydroxylated at conserved proline residues by HIF prolyl-hydroxylases, allowing their recognition and ubiquitination by the VHL E3 ubiquitin ligase, which labels them for rapid degradation by the proteasome. This occurs only in normoxic conditions. In hypoxic conditions, HIF prolyl-hydroxylase is inhibited, since it utilizes oxygen as a cosubstrate.
Inhibition of electron transfer in the succinate dehydrogenase complex due to mutations in the SDHB or SDHD genes can cause a build-up of succinate that inhibits HIF prolyl-hydroxylase, stabilizing HIF-1α. This is termed pseudohypoxia.
HIF-1, when stabilized by hypoxic conditions, upregulates several genes to promote survival in low-oxygen conditions. These include glycolysis enzymes, which allow ATP synthesis in an oxygen-independent manner, and vascular endothelial growth factor (VEGF), which promotes angiogenesis. HIF-1 acts by binding to HIF-responsive elements (HREs) in promoters that contain the sequence NCGTG.
It has been shown that muscle A kinase–anchoring protein (mAKAP) organized E3 ubiquitin ligases, affecting stability and positioning of HIF-1 inside its action site in the nucleus. Depletion of mAKAP or disruption of its targeting to the perinuclear (in cardiomyocytes) region altered the stability of HIF-1 and transcriptional activation of genes associated with hypoxia. Thus, "compartmentalization" of oxygen-sensitive signaling components may influence the hypoxic response.
The advanced knowledge of the molecular regulatory mechanisms of HIF1 activity under hypoxic conditions contrast sharply with the paucity of information on the mechanistic and functional aspects governing NF-κB mediated HIF1 regulation under normoxic conditions. However, HIF-1α stabilization is also found in non-hypoxic conditions through an, until recently, unknown mechanism. It was shown that NF-κB (nuclear factor κB) is a direct modulator of HIF-1α expression in the presence of normal oxygen pressure. siRNA (small interfering RNA) studies for individual NF-κB members revealed differential effects on HIF-1α mRNA levels, indicating that NF-κB can regulate basal HIF-1α expression. Finally, it was shown that when endogenous NF-κB is induced by TNFα (tumour necrosis factor α) treatment, HIF-1α levels also change in an NF-κB-dependent manner. HIF-1 and HIF-2 have different physiological roles. HIF-2 regulates erythropoietin production in adult life.
As a therapeutic target
Recently several drugs have been developed which act as selective HIF prolyl-hydroxylase inhibitors. The most notable of these include FibroGen's compounds FG-2216 and FG-4592, both are intended as orally acting drugs for use in the treatment of forms of anemia. By inhibiting HIF prolyl-hydroxylase, the stability of HIF-2α in the kidney is increased, which results in an increase in endogenous production of erythropoietin. Both of these drugs made it through to phase II clinical trials, but these were suspended temporarily in May 2007 following the death of a trial participant from fulminant hepatitis. However it is unclear whether this death was caused by FG-2216. The hold has been lifted in early 2008 as FDA has reviewed and approved a thorough response from FibroGen.
Inflammation and cancer
In other scenarios and in contrast to the therapy outlined above, recent research suggests that HIF induction in normoxia is likely to have serious consequences in disease settings with a chronic inflammatory component. It has also been shown that chronic inflammation is self-perpetuating and that it distorts the microenvironment as a result of aberrantly active transcription factors. Consequently, alterations in growth factor, chemokine, cytokine and ROS balance occur within the cellular milieu that in turn provide the axis of growth and survival needed for de novo development of cancer and metastasis. The results of a recently published study have numerous implications for a number of pathologies where NF-κB and HIF-1 are deregulated, including rheumatoid arthritis and cancer. Therefore, it is thought that understanding the cross talk between these two key transcription factors, NF-κB and HIF, will greatly enhance the process of drug development.
HIF activity is involved in angiogenesis required for cancer tumor growth, so HIF inhibitors such as phenethyl isothiocyanate and Acriflavine are under investigation for anti-cancer effects.
- Smith TG, Robbins PA, Ratcliffe PJ (May 2008). "The human side of hypoxia-inducible factor". Br. J. Haematol. 141 (3): 325–34. doi:10.1111/j.1365-2141.2008.07029.x. PMC 2408651. PMID 18410568.
- Wang GL, Jiang BH, Rue EA, Semenza GL (June 1995). "Hypoxia-inducible factor 1 is a basic helix-loop-helix-PAS heterodimer regulated by cellular O2 tension". Proc. Natl. Acad. Sci. U.S.A. 92 (12): 5510–4. doi:10.1073/pnas.92.12.5510. PMC 41725. PMID 7539918.
- Jiang BH, Rue E, Wang GL, Roe R, Semenza GL (July 1996). "Dimerization, DNA binding, and transactivation properties of hypoxia-inducible factor 1". J. Biol. Chem. 271 (30): 17771–8. doi:10.1074/jbc.271.30.17771. PMID 8663540.
- Zhulin IB, Taylor BL, Dixon R (September 1997). "PAS domain S-boxes in Archaea, Bacteria and sensors for oxygen and redox". Trends Biochem. Sci. 22 (9): 331–3. doi:10.1016/S0968-0004(97)01110-9. PMID 9301332.
- Ponting CP, Aravind L (November 1997). "PAS: a multifunctional domain family comes to light". Curr. Biol. 7 (11): R674–7. doi:10.1016/S0960-9822(06)00352-6. PMID 9382818.
- Yang J, Zhang L, Erbel PJ, Gardner KH, Ding K, Garcia JA, Bruick RK (October 2005). "Functions of the Per/ARNT/Sim domains of the hypoxia-inducible factor". J. Biol. Chem. 280 (43): 36047–54. doi:10.1074/jbc.M501755200. PMID 16129688.
- Min JH, Yang H, Ivan M, Gertler F, Kaelin WG, Pavletich NP (June 2002). "Structure of an HIF-1alpha -pVHL complex: hydroxyproline recognition in signaling". Science 296 (5574): 1886–9. doi:10.1126/science.1073440. PMID 12004076.
- Freedman SJ, Sun ZY, Poy F, et al. (April 2002). "Structural basis for recruitment of CBP/p300 by hypoxia-inducible factor-1 alpha". Proc. Natl. Acad. Sci. U.S.A. 99 (8): 5367–72. doi:10.1073/pnas.082117899. PMC 122775. PMID 11959990.
- Benizri E, Ginouvès A, Berra E (April 2008). "The magic of the hypoxia-signaling cascade". Cell. Mol. Life Sci. 65 (7-8): 1133–49. doi:10.1007/s00018-008-7472-0. PMID 18202826.
- Formenti F, Constantin-Teodosiu D, Emmanuel Y, Cheeseman J, Dorrington KL, Edwards LM, Humphreys SM, Lappin TR, McMullin MF, McNamara CJ, Mills W, Murphy JA, O'Connor DF, Percy MJ, Ratcliffe PJ, Smith TG, Treacy M, Frayn KN, Greenhaff PL, Karpe F, Clarke K, Robbins PA (July 2010). "Regulation of human metabolism by hypoxia-inducible factor". Proc. Natl. Acad. Sci. U.S.A. 107 (28): 12722–7. doi:10.1073/pnas.1002339107. PMC 2906567. PMID 20616028.
- Maxwell PH, Wiesener MS, Chang GW, Clifford SC, Vaux EC, Cockman ME, Wykoff CC, Pugh CW, Maher ER, Ratcliffe PJ (May 1999). "The tumour suppressor protein VHL targets hypoxia-inducible factors for oxygen-dependent proteolysis". Nature 399 (6733): 271–5. doi:10.1038/20459. PMID 10353251.
- Semenza GL (August 2004). "Hydroxylation of HIF-1: oxygen sensing at the molecular level". Physiology (Bethesda) 19 (4): 176–82. doi:10.1152/physiol.00001.2004. PMID 15304631.
- Wong W, Goehring AS, Kapiloff MS, Langeberg LK, Scott JD (2008). "mAKAP compartmentalizes oxygen-dependent control of HIF-1alpha". Sci Signal 1 (51): ra18. doi:10.1126/scisignal.2000026. PMC 2828263. PMID 19109240.
- van Uden P, Kenneth NS, Rocha S (2008). "Regulation of hypoxia-inducible factor-1alpha by NF-kappaB". Biochem J. 412 (3): 477–484. doi:10.1042/BJ20080476. PMC 2474706. PMID 18393939.
- Haase VH (July 2010). "Hypoxic regulation of erythropoiesis and iron metabolism". Am. J. Physiol. Renal Physiol. 299 (1): F1–13. doi:10.1152/ajprenal.00174.2010. PMC 2904169. PMID 20444740.
- Bruegge K, Jelkmann W, Metzen E (2007). "Hydroxylation of hypoxia-inducible transcription factors and chemical compounds targeting the HIF-alpha hydroxylases". Curr. Med. Chem. 14 (17): 1853–62. doi:10.2174/092986707781058850. PMID 17627521.
- Dead URL FG-2216: Anemia
- Cases A (December 2007). "The latest advances in kidney diseases and related disorders". Drug news & perspectives 20 (10): 647–54. ISSN 0214-0934. PMID 18301799.
- Hsieh MM, Linde NS, Wynter A, Metzger M, Wong C, Langsetmo I, Lin A, Smith R, Rodgers GP, Donahue RE, Klaus SJ, Tisdale JF (September 2007). "HIF prolyl hydroxylase inhibition results in endogenous erythropoietin induction, erythrocytosis, and modest fetal hemoglobin expression in rhesus macaques". Blood 110 (6): 2140–7. doi:10.1182/blood-2007-02-073254. PMC 1976368. PMID 17557894.
- The FDA Accepts the Complete Response for Clinical Holds of FG-2216/FG-4592 for the Treatment of Anemia
- Lee, K.; Zhang, H.; Qian, D. Z.; Rey, S.; Liu, J. O.; Semenza, G. L. (2009). "Acriflavine inhibits HIF-1 dimerization, tumor growth, and vascularization". Proceedings of the National Academy of Sciences 106 (42): 17910. doi:10.1073/pnas.0909353106.
- Syed Alwi SS, Cavell BE, Telang U, Morris ME, Parry BM, Packham G (November 2010). "In vivo modulation of 4E binding protein 1 (4E-BP1) phosphorylation by watercress: a pilot study". Br. J. Nutr. 104 (9): 1288–96. doi:10.1017/S0007114510002217. PMID 20546646.
- Semenza GL (October 2007). "Evaluation of HIF-1 inhibitors as anticancer agents". Drug Discov. Today 12 (19-20): 853–9. doi:10.1016/j.drudis.2007.08.006. PMID 17933687.
- Melillo G (September 2006). "Inhibiting hypoxia-inducible factor 1 for cancer therapy". Mol. Cancer Res. 4 (9): 601–5. doi:10.1158/1541-7786.MCR-06-0235. PMID 16940159.
- Adamcio, B.; Sperling, S.; Hagemeyer, N.; Walkinshaw, G.; Ehrenreich, H. (2010). "Hypoxia inducible factor stabilization leads to lasting improvement of hippocampal memory in healthy mice". Behavioural Brain Research 208 (1): 80–84. doi:10.1016/j.bbr.2009.11.010. PMID 19900484.
This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.
HIF-1 alpha C terminal transactivation domain Provide feedback
Hypoxia inducible factor-1 alpha (HIF-1 alpha) is the regulatory subunit of the heterodimeric transcription factor HIF-1. It plays a key role in cellular response to low oxygen tension. This region corresponds to the C terminal transactivation domain.
Freedman SJ, Sun ZY, Poy F, Kung AL, Livingston DM, Wagner G, Eck MJ; , Proc Natl Acad Sci U S A. 2002;99:5367-5372.: Structural basis for recruitment of CBP/p300 by hypoxia-inducible factor-1 alpha. PUBMED:11959990 EPMC:11959990
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR014887
Hypoxia inducible factor-1 alpha (HIF-1 alpha) is the regulatory subunit of the heterodimeric transcription factor HIF-1. It plays a key role in cellular response to low oxygen tension. This region corresponds to the C-terminal transactivation domain.
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
The graphic that is shown by default represents the longest sequence with a given architecture. Each row contains the following information:
- the number of sequences which exhibit this architecture
a textual description of the architecture, e.g. Gla, EGF x 2, Trypsin.
This example describes an architecture with one
Gladomain, followed by two consecutive
EGFdomains, and finally a single
- a link to the page in the Pfam site showing information about the sequence that the graphic describes
- the UniProt description of the protein sequence
- the number of residues in the sequence
- the Pfam graphic itself.
Note that you can see the family page for a particular domain by clicking on the graphic. You can also choose to see all sequences which have a given architecture by clicking on the Show link in each row.
Finally, because some families can be found in a very large number of architectures, we load only the first fifty architectures by default. If you want to see more architectures, click the button at the bottom of the page to load the next set.
Loading domain graphics...
We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database using the family HMM. We also generate alignments using four representative proteomes (RP) sets, the NCBI sequence database, and our metagenomics sequence database. More...
There are various ways to view or download the sequence alignments that we store. We provide several sequence viewers and a plain-text Stockholm-format file for download.
We make a range of alignments for each Pfam-A family:
- the curated alignment from which the HMM for the family is built
- the alignment generated by searching the sequence database using the HMM
- Representative Proteomes (RPs) at 15%, 35%, 55% and 75% co-membership thresholds
- alignment generated by searching the NCBI sequence database using the family HMM
- alignment generated by searching the metagenomics sequence database using the family HMM
You can see the alignments as HTML or in three different sequence viewers:
- a Java applet developed at the University of Dundee. You will need Java installed before running jalview
- an HTML page showing the whole alignment.Please note: full Pfam alignments can be very large. These HTML views are extremely large and often cause problems for browsers. Please use either jalview or the Pfam viewer if you have trouble viewing the HTML version
- an HTML-based representation of the alignment, coloured according to the posterior-probability (PP) values from the HMM. As for the standard HTML view, heatmap alignments can also be very large and slow to render.
- Pfam viewer
- an HTML-based viewer that uses DAS to retrieve alignment fragments on request
You can download (or view in your browser) a text representation of a Pfam alignment in various formats:
You can also change the order in which sequences are listed in the alignment, change how insertions are represented, alter the characters that are used to represent gaps in sequences and, finally, choose whether to download the alignment or to view it in your browser directly.
You may find that large alignments cause problems for the viewers and the reformatting tool, so we also provide all alignments in Stockholm format. You can download either the plain text alignment, or a gzipped version of it.
We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.
1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
Format an alignment
We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.
You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.
MyHits provides a collection of tools to handle multiple sequence alignments. For example, one can refine a seed alignment (sequence addition or removal, re-alignment or manual edition) and then search databases for remote homologs using HMMER3.
HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...
If you find these logos useful in your own work, please consider citing the following article:
This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.
Note: You can also download the data file for the tree.
Curation and family details
This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.
|Number in seed:||15|
|Number in full:||244|
|Average length of the domain:||38.70 aa|
|Average identity of full alignment:||68 %|
|Average coverage of the sequence by the domain:||4.98 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||5|
|Download:||download the raw HMM for this family|
Weight segments by...
Change the size of the sunburst
selected sequences to HMM
a FASTA-format file
- 0 sequences
- 0 species
This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the More....
This chart is a modified "sunburst" visualisation of the species tree for this family. It shows each node in the tree as a separate arc, arranged radially with the superkingdoms at the centre and the species arrayed around the outermost ring.
How the sunburst is generated
The tree is built by considering the taxonomic lineage of each sequence that has a match to this family. For each node in the resulting tree, we draw an arc in the sunburst. The radius of the arc, its distance from the root node at the centre of the sunburst, shows the taxonomic level ("superkingdom", "kingdom", etc). The length of the arc represents either the number of sequences represented at a given level, or the number of species that are found beneath the node in the tree. The weighting scheme can be changed using the sunburst controls.
In order to reduce the complexity of the representation, we reduce the number of taxonomic levels that we show. We consider only the following eight major taxonomic levels:
Colouring and labels
Segments of the tree are coloured approximately according to their superkingdom. For example, archeal branches are coloured with shades of orange, eukaryotes in shades of purple, etc. The colour assignments are shown under the sunburst controls. Where space allows, the name of the taxonomic level will be written on the arc itself.
As you move your mouse across the sunburst, the current node will be highlighted. In the top section of the controls panel we show a summary of the lineage of the currently highlighed node. If you pause over an arc, a tooltip will be shown, giving the name of the taxonomic level in the title and a summary of the number of sequences and species below that node in the tree.
Anomalies in the taxonomy tree
There are some situations that the sunburst tree cannot easily handle and for which we have work-arounds in place.
Missing taxonomic levels
Some species in the taxonomic tree may not have one or more of the main eight levels that we display. For example, Bos taurus is not assigned an order in the NCBI taxonomic tree. In such cases we mark the omitted level with, for example, "No order", in both the tooltip and the lineage summary.
Unmapped species names
The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.
So that these nodes are not simply omitted from the sunburst tree, we group them together in a separate branch (or segment of the sunburst tree). Since we cannot determine the lineage for these unmapped species, we show all levels between the superkingdom and the species as "uncategorised".
Since we reduce the species tree to only the eight main taxonomic levels, sequences that are mapped to the sub-species level in the tree would not normally be shown. Rather than leave out these species, we map them instead to their parent species. So, for example, for sequences belonging to one of the Vibrio cholerae sub-species in the NCBI taxonomy, we show them instead as belonging to the species Vibrio cholerae.
Too many species/sequences
For large species trees, you may see blank regions in the outer layers of the sunburst. These occur when there are large numbers of arcs to be drawn in a small space. If an arc is less than approximately one pixel wide, it will not be drawn and the space will be left blank. You may still be able to get some information about the species in that region by moving your mouse across the area, but since each arc will be very small, it will be difficult to accurately locate a particular species.
The tree shows the occurrence of this domain across different species. More...
We show the species tree in one of two ways. For smaller trees we try to show an interactive representation, which allows you to select specific nodes in the tree and view them as an alignment or as a set of Pfam domain graphics.
Unfortunately we have found that there are problems viewing the interactive tree when the it becomes larger than a certain limit. Furthermore, we have found that Internet Explorer can become unresponsive when viewing some trees, regardless of their size. We therefore show a text representation of the species tree when the size is above a certain limit or if you are using Internet Explorer to view the site.
If you are using IE you can still load the interactive tree by clicking the "Generate interactive tree" button, but please be aware of the potential problems that the interactive species tree can cause.
For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.
We also count the number of unique sequences on which each domain is found, which is shown in green. Note that a domain may appear multiple times on the same sequence, leading to the difference between these two numbers.
Finally, we group sequences from the same organism according to the NCBI code that is assigned by UniProt, allowing us to count the number of distinct sequences on which the domain is found. This value is shown in the pink boxes.
We use the NCBI species tree to group organisms according to their taxonomy and this forms the structure of the displayed tree. Note that in some cases the trees are too large (have too many nodes) to allow us to build an interactive tree, but in most cases you can still view the tree in a plain text, non-interactive representation. Those species which are represented in the seed alignment for this domain are highlighted.
You can use the tree controls to manipulate how the interactive tree is displayed:
- show/hide the summary boxes
- highlight species that are represented in the seed alignment
- expand/collapse the tree or expand it to a given depth
- select a sub-tree or a set of species within the tree and view them graphically or as an alignment
- save a plain text representation of the tree
Please note: for large trees this can take some time. While the tree is loading, you can safely switch away from this tab but if you browse away from the family page entirely, the tree will not be loaded.
There is 1 interaction for this family. More...
We determine these interactions using iPfam, which considers the interactions between residues in three-dimensional protein structures and maps those interactions back to Pfam families. You can find more information about the iPfam algorithm in the journal article that accompanies the website.
For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the HIF-1a_CTAD domain has been found. There are 5 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.
Loading structure mapping...