0  structures 190  species 193  sequences

Family: SAM-III (RF01767)

Description: SAM-III riboswitch aptamer (SMK box)

Summary

Note on Riboswitches

This Rfam family SAM-III (RF01767) represents an aptamer domain of a full riboswitch SAM-III riboswitch aptamer (SMK box). Riboswitches are non-coding RNA structures that regulate gene expression in response to ligand. Each riboswitch has two main parts: the aptamer domain and the expression platform. The aptamer domain is highly conserved to precisely bind its ligand. However, the expression platform has multiple modes of gene regulation, which introduces sequence and structure variability that increases difficulty in its detection through covariance model searching. For more information see the original publications.

Wikipedia annotation Edit Wikipedia article

The Rfam group coordinates the annotation of Rfam families in Wikipedia. This family is described by a Wikipedia entry SMK box riboswitch. More...

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

Sequences

Alignment

There are various ways to view or download the seed alignments that we store. You can use a sequence viewer to look at them, or you can look at a plain text version of the sequence in a variety of different formats. More...

View options

You can view Rfam seed alignments in your browser in various ways. Choose the viewer that you want to use and click the "View" button to show the alignment in a pop-up window.

Viewer:

Formatting options

You can view or download Rfam seed alignments in several formats. Check either the "download" button, to save the formatted alignment, or "view", to see it in your browser window, and click "Generate".

Alignment format:
Download/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.

Secondary structure

This section shows a variety of different secondary structure representations for this family. More...

You can view the secondary structure of the family using the VARNA applet. You can see more information about VARNA iself here.

Species distribution

Sunburst controls

Hide

Weight segments by...


Change the size of the sunburst

Small
Large

Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence

Selections

Click on a node to select that node and its sub-tree.

Clear selection

This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

Tree controls

Hide

The tree shows the occurrence of this RNA across different species. More...

Loading...

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.

Trees

This page displays the predicted phylogenetic tree for the alignment. More...

This tree was built using the fasttree method.

Label the trees using or

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

References

This section shows the database cross-references that we have for this Rfam family.

Literature references

  1. Fuchs RT, Grundy FJ, Henkin TM Proc Natl Acad Sci U S A. 2007;104:4876-4880. S-adenosylmethionine directly inhibits binding of 30S ribosomal subunits to the SMK box translational riboswitch RNA. PUBMED:17360376

  2. Fuchs RT, Grundy FJ, Henkin TM Nat Struct Mol Biol. 2006;13:226-233. The S(MK) box is a new SAM-binding RNA for translational regulation of SAM synthetase. PUBMED:16491091

  3. Lu C, Smith AM, Fuchs RT, Ding F, Rajashankar K, Henkin TM, Ke A Nat Struct Mol Biol. 2008;15:1076-1083. Crystal structures of the SAM-III/S(MK) riboswitch reveal the SAM-dependent translation inhibition mechanism. PUBMED:18806797

  4. Wang JX, Breaker RR Biochem Cell Biol. 2008;86:157-168. Riboswitches that sense S-adenosylmethionine and S-adenosylhomocysteine. PUBMED:18443629

  5. Wang JX, Lee ER, Morales DR, Lim J, Breaker RR Mol Cell. 2008;29:691-702. Riboswitches that sense S-adenosylhomocysteine and activate genes involved in coenzyme recycling. PUBMED:18374645

External database links

Curation and family details

This section shows the detailed information about the Rfam family. We're happy to receive updated or improved alignments for new or existing families. Submit your new alignment and we'll take a look.

Curation

Seed source Gardner PP
Structure source Published; PMID:18806797; Gardner PP
Type Cis-reg; riboswitch;
Author Gardner PPORCID logo
Alignment details
Alignment Number of
sequences
full 168
seed 25

Model information

Build commands
cmbuild -F CM SEED
cmcalibrate --mpi CM
Search command
cmsearch --cpu 4 --verbose --nohmmonly -T 30.00 -Z 2958934 CM SEQDB
Gathering cutoff 45.0
Trusted cutoff 45.1
Noise cutoff 44.9
Covariance model Download