The Wikipedia text that you see displayed on our web site was retrieved from Wikipedia. This means that the information we display is a copy of the information from the Wikipedia database. The button above ("Edit wikipedia entry") takes you to the edit page for the article directly within Wikipedia.

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:

• Five pillars
• Policies and quidelines
• Wikipedia help contents
• Wikipedia Tips
• Editing help

Things you should know

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 entry" 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 rfam-help@ebi.ac.uk and we will try to help.

Information we would like to see added

We would value contributions that are referenced directly to the primary literature. Information on structure and function will be especially valuable.

Adding references is explained by this Wikipedia how-to article.

For a good example of what is possible in wikipedia, look at the Hammerhead Ribozyme entry.

Does Rfam agree with the content of the Wikipedia entry ?

Rfam has chosen to create Wikipedia entries for all of our RNA families and to open them up to community annotation. While the original Wikipedia article that we import was (in most cases) generated from Rfam annotations, the Wikipedia article you see now may bear little resemblance to that original text. 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 Rfam does not curate the Wikipedia entries and we cannot guarantee the accuracy of the information on the Wikipedia page.

Contact us

If you have problems editing or experience problems with these pages please contact us.

If you are interested in contributing to a wide range of articles relating to RNA, see the Wikiproject RNA page.

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Seed alignment view

Download

Download a gzip-compressed, Stockholm-format file containing the seed alignment for this family. You may find RALEE useful when viewing sequence alignments.

Submit a new alignment

We're happy receive updated seed alignments for new or existing families. Submit your new alignment and we'll take a look.

In this page you can view static images showing the secondary structure of this family using a variety of colouring schemes:

Conservation (cons): this plot colours each character by how well conserved it is. A site with 100% sequence conservation is coloured red, 0% is violet.

Covariation (cov): this plot colours each base-pair according to how much the corresponding nucleotides are co-varying. A base-pair position at which every pair of nucleotides is co-variant with respect to every other pair in the alignment gets a score of 2 and is coloured red. Conversely, a base-pair position at every pair is anti-co-variant with respect to every other pair (e.g. lots of mutations to non-canonical pairs) gets a score of -2 and is coloured violet. Further information on this metric can be found in this document.

Sequence entropy (ent): this plot colours each character by how under- or over-represented the residues at the site are. Sites where one or more nucleotides are over-represented while the other nucleotides are either non-existent or near the background frequencies, receive positive scores; sites where all the nucleotides are under-represented receive negative scores. Further information on this metric can be found in this document.

Fraction of canonical basepairs (fcbp): this plot colours each base-pair by the percentage of canonical basepairs (A:U, C:G, G:U) which are found in the corresponding position in the alignment. A pair of sites with 100% canonical pairs is coloured red, a site with 0% is violet.

Maximum parse of the covariance model (maxcm): this plot takes the covariance model for the family and generates the sequence with the maximum possible score for that model. Each character is coloured by how many bits it contributes to the total score.

Sequence: for most of the above cases, the representative sequence used for the backbone is the most informative sequence (MIS). Any residue that has a higher frequency than than the background frequency is projected into the IUPAC redundancy codes.

Normal: this plot simply colours each stem loop

R-chie (rchie): arc diagrams showing secondary structure, calculated using the R-chie package. The consensus secondary structure is visualized as arc diagrams on top of each diagram, where a basepair in an arc, connect two columns of the block of sequences below. The block of sequences below represent the multiple sequence alignment of the Rfam seed, where each sequence is a horizontal strip. Sequences in the alignments are ordered so sequences that best fit the structure are on top, and those that do not fit as well are towards the bottom. For seed alignments for over 500 sequences, 500 random sequences were chosen. Rfam entries without sturcture have a blank plot. Colour information can be found on the R-chie FAQ.

You can also view the secondary structure in the VARNA applet. The applet is shown in a separate pop-up window.

Acknowledgements

The bulk of the code for generating these graphics was kindly supplied by Andreas Gruber and Ivo Hofacker. The statistics were implemented by Rfam.

The VARNA applet is developed by Yann Ponty et al:

The R-chie arc diagrams were calculated using R-chie:

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These trees were generated using either a maximum likelihood approach or neighbour-joining. If the number of sequences in the alignment was less than or equal to 64 then the maximum likelihood approach of Rivas and Eddy was used [1]. For families with more than 64 sequences in the alignment the neighbour-joining approach with F84 distances as implemented in phylip was used [2].

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This tree was built using the fasttree method.

Label the trees using species names or accessions.

Note: You can also download the data file for the seed tree.

We do not have tree information for this family. This is most likely due to the size of the family and the number of species covered. For very large families it is too computationally expensive to calculate trees and the resulting tree images would be too large to display in a browser.