Summary: Leucine rich repeats (6 copies)

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Wikipedia: Leucine-rich repeat
Pfam
InterPro

This is the Wikipedia entry entitled "Leucine-rich repeat". More...

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Leucine-rich repeat Edit Wikipedia article

An example of a leucine-rich repeat protein, a porcine ribonuclease inhibitor

Identifiers

Symbol

LRR_1

Pfam clan

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe; PDBj
PDBsum	structure summary

Leucine rich repeat variant

a leucine-rich repeat variant with a novel repetitive protein structural motif

Identifiers

Symbol

LRV

Pfam clan

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe; PDBj
PDBsum	structure summary

LRR adjacent

internalin h: crystal structure of fused n-terminal domains.

Identifiers

Symbol

LRR_adjacent

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe; PDBj
PDBsum	structure summary

Leucine rich repeat N-terminal domain

dimeric bovine tissue-extracted decorin, crystal form 2

Identifiers

Symbol

LRRNT

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe; PDBj
PDBsum	structure summary

Leucine rich repeat N-terminal domain

the crystal structure of pgip (polygalacturonase inhibiting protein), a leucine rich repeat protein involved in plant defense

Identifiers

Symbol

LRRNT_2

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe; PDBj
PDBsum	structure summary

Leucine rich repeat C-terminal domain

third lrr domain of drosophila slit

Identifiers

Symbol

LRRCT

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe; PDBj
PDBsum	structure summary

LRV protein FeS4 cluster

a leucine-rich repeat variant with a novel repetitive protein structural motif

Identifiers

Symbol

LRV_FeS

Pfam clan

Available protein structures:
Pfam	structures
PDB	RCSB PDB; PDBe; PDBj
PDBsum	structure summary

A leucine-rich repeat (LRR) is a protein structural motif that forms an α/β horseshoe fold.^[1]^[2] It is composed of repeating 20–30 amino acid stretches that are unusually rich in the hydrophobic amino acid leucine. These repeats commonly fold together to form a solenoid protein domain, termed leucine-rich repeat domain. Typically, each repeat unit has beta strand-turn-alpha helix structure, and the assembled domain, composed of many such repeats, has a horseshoe shape with an interior parallel beta sheet and an exterior array of helices. One face of the beta sheet and one side of the helix array are exposed to solvent and are therefore dominated by hydrophilic residues. The region between the helices and sheets is the protein's hydrophobic core and is tightly sterically packed with leucine residues.

Leucine-rich repeats are frequently involved in the formation of protein–protein interactions.^[3]^[4]

Examples

Leucine-rich repeat motifs have been identified in a large number of functionally unrelated proteins.^[5] The best-known example is the ribonuclease inhibitor, but other proteins such as the tropomyosin regulator tropomodulin and the toll-like receptor also share the motif. In fact, the toll-like receptor possesses 10 successive LRR motifs which serve to bind pathogen- and danger-associated molecular patterns.

Although the canonical LRR protein contains approximately one helix for every beta strand, variants that form beta-alpha superhelix folds sometimes have long loops rather than helices linking successive beta strands.

One leucine-rich repeat variant domain (LRV) has a novel repetitive structural motif consisting of alternating alpha- and 3(10)-helices arranged in a right-handed superhelix, with the absence of the beta-sheets present in other leucine-rich repeats.^[6]

Associated domains

Leucine-rich repeats are often flanked by N-terminal and C-terminal cysteine-rich domains, but not always as is the case with C5orf36

They also co-occur with LRR adjacent domains. These are small, all beta strand domains, which have been structurally described for the protein Internalin (InlA) and related proteins InlB, InlE, InlH from the pathogenic bacterium Listeria monocytogenes. Their function appears to be mainly structural: They are fused to the C-terminal end of leucine-rich repeats, significantly stabilising the LRR, and forming a common rigid entity with the LRR. They are themselves not involved in protein-protein-interactions but help to present the adjacent LRR-domain for this purpose. These domains belong to the family of Ig-like domains in that they consist of two sandwiched beta sheets that follow the classical connectivity of Ig-domains. The beta strands in one of the sheets is, however, much smaller than in most standard Ig-like domains, making it somewhat of an outlier.^[7]^[8]^[9]

An iron sulphur cluster is found at the N-terminus of some proteins containing the leucine-rich repeat variant domain (LRV). These proteins have a two-domain structure, composed of a small N-terminal domain containing a cluster of four Cysteine residues that houses the 4Fe:4S cluster, and a larger C-terminal domain containing the LRV repeats.^[6] Biochemical studies revealed that the 4Fe:4S cluster is sensitive to oxygen, but does not appear to have reversible redox activity.

References

^ Kobe B, Deisenhofer J (October 1994). "The leucine-rich repeat: a versatile binding motif". Trends Biochem. Sci. 19 (10): 415–21. doi:10.1016/0968-0004(94)90090-6. PMID 7817399.
^ Enkhbayar P, Kamiya M, Osaki M, Matsumoto T, Matsushima N (February 2004). "Structural principles of leucine-rich repeat (LRR) proteins". Proteins. 54 (3): 394–403. doi:10.1002/prot.10605. PMID 14747988.
^ Kobe B, Kajava AV (December 2001). "The leucine-rich repeat as a protein recognition motif". Curr. Opin. Struct. Biol. 11 (6): 725–32. doi:10.1016/S0959-440X(01)00266-4. PMID 11751054.
^ Gay NJ, Packman LC, Weldon MA, Barna JC (October 1991). "A leucine-rich repeat peptide derived from the Drosophila Toll receptor forms extended filaments with a beta-sheet structure". FEBS Lett. 291 (1): 87–91. doi:10.1016/0014-5793(91)81110-T. PMID 1657640.
^ Rothberg JM, Jacobs JR, Goodman CS, Artavanis-Tsakonas S (December 1990). "slit: an extracellular protein necessary for development of midline glia and commissural axon pathways contains both EGF and LRR domains". Genes Dev. 4 (12A): 2169–87. doi:10.1101/gad.4.12a.2169. PMID 2176636.
^ ^a ^b Peters JW, Stowell MH, Rees DC (December 1996). "A leucine-rich repeat variant with a novel repetitive protein structural motif". Nat. Struct. Biol. 3 (12): 991–4. doi:10.1038/nsb1296-991. PMID 8946850.
^ Schubert WD, Gobel G, Diepholz M, Darji A, Kloer D, Hain T, Chakraborty T, Wehland J, Domann E, Heinz DW (September 2001). "Internalins from the human pathogen Listeria monocytogenes combine three distinct folds into a contiguous internalin domain". J. Mol. Biol. 312 (4): 783–94. doi:10.1006/jmbi.2001.4989. PMID 11575932.
^ Schubert WD, Urbanke C, Ziehm T, Beier V, Machner MP, Domann E, Wehland J, Chakraborty T, Heinz DW (December 2002). "Structure of internalin, a major invasion protein of Listeria monocytogenes, in complex with its human receptor E-cadherin". Cell. 111 (6): 825–36. doi:10.1016/S0092-8674(02)01136-4. PMID 12526809.
^ Freiberg A, Machner MP, Pfeil W, Schubert WD, Heinz DW, Seckler R (March 2004). "Folding and stability of the leucine-rich repeat domain of internalin B from Listeri monocytogenes". J. Mol. Biol. 337 (2): 453–61. doi:10.1016/j.jmb.2004.01.044. PMID 15003459.

External links

v t e Protein tertiary structure

General	Structural domain Protein folding Structure determination methods

All-α folds:	Helix bundle Globin fold Homeodomain fold Alpha solenoid

All-β folds:	Immunoglobulin domain Beta barrel Beta-propeller

α/β folds:	TIM barrel Leucine-rich repeat Flavodoxin fold Rossmann fold Thioredoxin fold Trefoil knot fold

α+β folds:	DNA clamp Ferredoxin fold Ribonuclease A SH2-like fold

Irregular folds:	Conotoxin

This article incorporates text from the public domain Pfam and InterPro IPR012569

This article incorporates text from the public domain Pfam and InterPro IPR013210

This article incorporates text from the public domain Pfam and InterPro IPR000372

This article incorporates text from the public domain Pfam and InterPro IPR000483

This article incorporates text from the public domain Pfam and InterPro IPR004830

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

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.

Leucine rich repeats (6 copies) Provide feedback

This family includes a number of leucine rich repeats. This family contains a large number of BSPA-like surface antigens from Trichomonas vaginalis.

Internal database links

SCOOP:	DUF285 FNIP LRR_4 LRR_8 LRR_9 LRRNT
Similarity to PfamA using HHSearch:	LRR_8 LRR_8

This tab holds annotation information from the InterPro database.

InterPro entry IPR026906

This entry represents a leucine rich repeat. A leucine-rich repeat (LRR) is a protein structural motif that forms an alpha/beta horseshoe fold [PUBMED:7817399, PUBMED:14747988]. Leucine-rich repeats are frequently involved in the formation of protein protein interactions [PUBMED:11751054, PUBMED:1657640].

This repeat is found in a large number of BSPA-like surface antigens from Trichomonas vaginalis.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan LRR (CL0022), which has the following description:

Each Leucine Rich Repeat is composed of a beta-alpha unit. These units form elongated non-globular structures. Leucine Rich Repeats are often flanked by cysteine rich domains. This Pfam entry contains Leucine Rich Repeats not recognised by the Pfam:PF00560 model.

The clan contains the following 11 members:

DUF285 FNIP LRR_1 LRR_2 LRR_3 LRR_4 LRR_5 LRR_6 LRR_8 LRR_9 Recep_L_domain

Alignments

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 (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets, the UniProtKB sequence database, 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.

Alignment types

We make a range of alignments for each Pfam-A family:

seed: the curated alignment from which the HMM for the family is built
full: the alignment generated by searching the sequence database using the HMM
RP15/RP35/RP55/RP75: Representative Proteomes (RPs) at 15%, 35%, 55% and 75% co-membership thresholds
UniProt: alignment generated by searching the UniProtKB sequence database using the family HMM
NCBI: alignment generated by searching the NCBI sequence database using the family HMM
meta: alignment generated by searching the metagenomics sequence database using the family HMM

Viewing

You can see the alignments as HTML or in three different sequence viewers:

jalview: a Java applet developed at the University of Dundee. You will need Java installed before running jalview
HTML: 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
PP/Heatmap: 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.

Reformatting

You can download (or view in your browser) a text representation of a Pfam alignment in various formats:

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Stockholm
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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.

Downloading

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.

View options

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.

	Seed (165)	Full (17281)	Representative proteomes				UniProt (30249)	NCBI (146915)	Meta (1380)
	Seed (165)	Full (17281)	RP15 (8412)	RP35 (14026)	RP55 (17135)	RP75 (20368)	UniProt (30249)	NCBI (146915)	Meta (1380)
Jalview	View	View	View	View	View	View	View	View	View
HTML	View
PP/heatmap	₁

¹Cannot generate PP/Heatmap alignments for seeds; no PP data available

Key: available, not generated, — not available.

Format an alignment

	Seed (165)	Full (17281)	Representative proteomes				UniProt (30249)	NCBI (146915)	Meta (1380)
	Seed (165)	Full (17281)	RP15 (8412)	RP35 (14026)	RP55 (17135)	RP75 (20368)	UniProt (30249)	NCBI (146915)	Meta (1380)
Alignment:
Format:
Order:	Tree Alphabetical
Sequence:	Inserts lower case All upper case
Gaps:
Download/view:	Download View

Download options

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.

	Seed (165)	Full (17281)	Representative proteomes				UniProt (30249)	NCBI (146915)	Meta (1380)
	Seed (165)	Full (17281)	RP15 (8412)	RP35 (14026)	RP55 (17135)	RP75 (20368)	UniProt (30249)	NCBI (146915)	Meta (1380)
Raw Stockholm	Download	Download	Download	Download	Download	Download	Download	Download	Download
Gzipped	Download	Download	Download	Download	Download	Download	Download	Download	Download

You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

HMM logo

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...

Trees

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.

Curation

Seed source:

Jackhmmer:Q7P2P7

Previous IDs:

none

Type:

Repeat

Author:

Bateman A

Number in seed:

165

Number in full:

17281

Average length of the domain:

112.10 aa

Average identity of full alignment:

18 %

Average coverage of the sequence by the domain:

46.24 %

HMM information

HMM build commands:

build method: hmmbuild -o /dev/null HMM SEED

search method: hmmsearch -Z 26740544 -E 1000 --cpu 4 HMM pfamseq

Model details:

Parameter	Sequence	Domain
Gathering cut-off	27.0	10.0
Trusted cut-off	27.0	10.0
Noise cut-off	26.9	9.9

Model length:

128

Family (HMM) version:

5

Download:

download the raw HMM for this family

Species distribution

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Colour assignments

Archea	Eukaryota
Bacteria	Other sequences
Viruses	Unclassified
Viroids	Unclassified sequence

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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...

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:

superkingdom
kingdom
phylum
class
order
family
genus
species

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".

Sub-species

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.

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

Species trees

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.

Interactive tree

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:

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Interactions

There are 7 interactions for this family. More...

Big_3 LRRNT LRR_1 LRR_5 LRR_8 Laminin_N Flagellin_C

Structures

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 LRR_5 domain has been found. There are 64 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...

v t e Protein domains

BAR BIR BZIP CARD C1 C2 DED ENTH FYVE HEAT Kringle LIM LRR NACHT PAS PDZ Pyrin PH PX SH2 SH3 SUN TRIO WD40 zinc finger

Family: LRR_5 (PF13306)

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Summary: Leucine rich repeats (6 copies)

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Leucine-rich repeat Edit Wikipedia article

Contents

Examples

Associated domains

See also

References

Further reading

External links

Leucine rich repeats (6 copies) Provide feedback

Internal database links

InterPro entry IPR026906

Domain organisation

Pfam Clan

Alignments

Alignment types

Viewing

Reformatting

Downloading

View options

Format an alignment

Download options

HMM logo

Trees

Curation and family details

Curation

HMM information

Species distribution

Sunburst controls

Weight segments by...

Change the size of the sunburst

Colour assignments

Selections

Currently selected:

How the sunburst is generated

Colouring and labels

Anomalies in the taxonomy tree

Missing taxonomic levels

Unmapped species names

Sub-species

Too many species/sequences

Tree controls

Annotation

Download tree

Selected sequences

Species trees

Interactive tree

Interactions

Structures