Please note: this site relies heavily on the use of javascript. Without a javascript-enabled browser, this site will not function correctly. Please enable javascript and reload the page, or switch to a different browser.
82  structures 1389  species 13  interactions 25597  sequences 4912  architectures

Family: LRR_1 (PF00560)

Summary: Leucine Rich Repeat

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 "Leucine-rich repeat". More...

Leucine-rich repeat Edit Wikipedia article

2bnh topview.png
An example of a leucine-rich repeat protein, a porcine ribonuclease inhibitor
Identifiers
Symbol LRR_1
Pfam PF00560
Pfam clan CL0022
InterPro IPR001611
SCOP 2bnh
SUPERFAMILY 2bnh
OPM protein 1xwd
Leucine rich repeat variant
PDB 1lrv EBI.jpg
a leucine-rich repeat variant with a novel repetitive protein structural motif
Identifiers
Symbol LRV
Pfam PF01816
Pfam clan CL0020
InterPro IPR004830
SCOP 1lrv
SUPERFAMILY 1lrv
LRR adjacent
PDB 1h6u EBI.jpg
internalin h: crystal structure of fused n-terminal domains.
Identifiers
Symbol LRR_adjacent
Pfam PF08191
InterPro IPR012569
Leucine rich repeat N-terminal domain
PDB 1xec EBI.jpg
dimeric bovine tissue-extracted decorin, crystal form 2
Identifiers
Symbol LRRNT
Pfam PF01462
InterPro IPR000372
SMART LRRNT
SCOP 1m10
SUPERFAMILY 1m10
Leucine rich repeat N-terminal domain
PDB 1ogq EBI.jpg
the crystal structure of pgip (polygalacturonase inhibiting protein), a leucine rich repeat protein involved in plant defense
Identifiers
Symbol LRRNT_2
Pfam PF08263
InterPro IPR013210
SMART LRRNT
SCOP 1m10
SUPERFAMILY 1m10
Leucine rich repeat C-terminal domain
PDB 1w8a EBI.jpg
third lrr domain of drosophila slit
Identifiers
Symbol LRRCT
Pfam PF01463
InterPro IPR000483
SMART LRRCT
SCOP 1m10
SUPERFAMILY 1m10
LRV protein FeS4 cluster
PDB 1lrv EBI.jpg
a leucine-rich repeat variant with a novel repetitive protein structural motif
Identifiers
Symbol LRV_FeS
Pfam PF05484
Pfam clan CL0020
InterPro IPR008665
SCOP 1lrv
SUPERFAMILY 1lrv

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[edit]

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[edit]

Leucine-rich repeats are often flanked by N-terminal and C-terminal cysteine-rich domains.

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.

See also[edit]

References[edit]

  1. ^ 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. 
  2. ^ 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. 
  3. ^ 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. 
  4. ^ 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. 
  5. ^ 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. 
  6. ^ 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. 
  7. ^ 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. 
  8. ^ 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. 
  9. ^ 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. 

Further reading[edit]

External links[edit]

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 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 is the Wikipedia entry entitled "Ribonuclease inhibitor". More...

Ribonuclease inhibitor Edit Wikipedia article

Leucine Rich Repeat
2bnh topview.png
Top view of porcine ribonuclease inhibitor, showing its horseshoe shape.[1] The outer layer is composed of α-helices and the inner layer of parallel β-strands. The inner and outer diameters are roughly 2.1 nm and 6.7 nm, respectively.
Identifiers
Symbol LRR_1
Pfam PF00560
Pfam clan CL0022
InterPro IPR003590
SMART SM00368
SCOP 1bnh
SUPERFAMILY 1bnh

Ribonuclease inhibitor (RI) is a large (~450 residues, ~49 kDa), acidic (pI ~4.7), leucine-rich repeat protein that forms extremely tight complexes with certain ribonucleases. It is a major cellular protein, comprising ~0.1% of all cellular protein by weight, and appears to play an important role in regulating the lifetime of RNA.[2]

RI has a surprisingly high cysteine content (~6.5%, cf. 1.7% in typical proteins) and is sensitive to oxidation. RI is also rich in leucine (21.5%, compared to 9% in typical proteins) and commensurately lower in other hydrophobic residues, esp. valine, isoleucine, methionine, tyrosine, and phenylalanine.

Structure

Side view of porcine ribonuclease inhibitor;[1] ribbon is colored from blue (N-terminus) to red (C-terminus).

RI is the classic leucine-rich repeat protein, consisting of alternating α-helices and β-strands along its backbone. These secondary structure elements wrap around in a curved, right-handed solenoid that resembles a horseshoe. The parallel β-strands and α-helices form the inner and outer wall of the horseshoe, respectively. The structure appears to be stabilized by buried asparagines at the base of each turn, as it passes from α-helix to β-strand. The αβ repeats alternate between 28 and 29 residues in length, effectively forming a 57-residue unit that corresponds to its genetic structure (each exon codes for a 57-residue unit).

Binding to ribonucleases

The affinity of RI for ribonucleases is perhaps the highest for any protein-protein interaction; the dissociation constant of the RI-RNase A complex is roughly 20 fM under physiological conditions while that for the RI-angiogenin complex is even smaller (<1 fM). Remarkably, RI is able to bind a wide variety of RNases, despite having low sequence identity. Structural studies indicate that RNases bind like a "cork in the bottle", associating especially with the C-terminal end of RI; the interaction is largely electrostatic but also buries a lot of surface area (>25 nm2). Efforts to mutate RNases to lower their affinity for RI while maintaining their enzymatic activity have had limited success. However, mammalian RI seems unable to bind a few amphibian ribonucleases[citation needed], such as ranpirnase (also known as Onconase).

RI's affinity for ribonucleases is important, since ribonucleases have cytotoxic and cytostatic effects (especially against cancer cells), and are under investigation as potential cancer therapeutics. Successful evasion of the ubiquitous RI would be essential for the success of a ribonuclease drug, (since it would be ineffective bound to RI). The frog protein Onconase is under investigation for treatment of skin cancers; unfortunately, the antigenicity of amphibian proteins makes them unsuitable for treating internal human cancers. Modifications of human ribonucleases that evade RI but retain their enzymatic activity have also been studied.

References

  1. ^ a b PDB 2BNH; Kobe B, Deisenhofer J (1993). "Crystal structure of porcine ribonuclease inhibitor, a protein with leucine-rich repeats". Nature 366 (6457): 751–6. doi:10.1038/366751a0. PMID 8264799. 
  2. ^ Shapiro R (2001). "Cytoplasmic ribonuclease inhibitor". Meth. Enzymol. 341: 611–28. doi:10.1016/S0076-6879(01)41180-3. PMID 11582809. 

Further reading

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 Repeat Provide feedback

CAUTION: This Pfam may not find all Leucine Rich Repeats in a protein. Leucine Rich Repeats are short sequence motifs present in a number of proteins with diverse functions and cellular locations. These repeats are usually involved in protein-protein interactions. 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.

Literature references

  1. Kobe B, Deisenhofer J; , Trends Biochem Sci 1994;19:415-421.: The leucine-rich repeat: a versatile binding motif. PUBMED:7817399 EPMC:7817399

  2. Kobe B, Deisenhofer J; , Nature 1993;366:751-756.: Crystal structure of porcine ribonuclease inhibitor, a protein with leucine-rich repeats. PUBMED:8264799 EPMC:8264799


Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR001611

Leucine-rich repeats (LRR) consist of 2-45 motifs of 20-30 amino acids in length that generally folds into an arc or horseshoe shape [PUBMED:14747988]. LRRs occur in proteins ranging from viruses to eukaryotes, and appear to provide a structural framework for the formation of protein-protein interactions [PUBMED:11751054, PUBMED:1657640].Proteins containing LRRs include tyrosine kinase receptors, cell-adhesion molecules, virulence factors, and extracellular matrix-binding glycoproteins, and are involved in a variety of biological processes, including signal transduction, cell adhesion, DNA repair, recombination, transcription, RNA processing, disease resistance, apoptosis, and the immune response [PUBMED:2176636].

Sequence analyses of LRR proteins suggested the existence of several different subfamilies of LRRs. The significance of this classification is that repeats from different subfamilies never occur simultaneously and have most probably evolved independently. It is, however, now clear that all major classes of LRR have curved horseshoe structures with a parallel beta sheet on the concave side and mostly helical elements on the convex side. At least six families of LRR proteins, characterised by different lengths and consensus sequences of the repeats, have been identified. Eleven-residue segments of the LRRs (LxxLxLxxN/CxL), corresponding to the beta-strand and adjacent loop regions, are conserved in LRR proteins, whereas the remaining parts of the repeats (herein termed variable) may be very different. Despite the differences, each of the variable parts contains two half-turns at both ends and a "linear" segment (as the chain follows a linear path overall), usually formed by a helix, in the middle. The concave face and the adjacent loops are the most common protein interaction surfaces on LRR proteins. 3D structure of some LRR proteins-ligand complexes show that the concave surface of LRR domain is ideal for interaction with alpha-helix, thus supporting earlier conclusions that the elongated and curved LRR structure provides an outstanding framework for achieving diverse protein-protein interactions [PUBMED:11751054]. Molecular modeling suggests that the conserved pattern LxxLxL, which is shorter than the previously proposed LxxLxLxxN/CxL is sufficient to impart the characteristic horseshoe curvature to proteins with 20- to 30-residue repeats [PUBMED:11967365].

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

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

Loading domain graphics...

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_7 LRR_8 LRR_9

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 using the family HMM. We also generate alignments using four representative proteomes (RP) sets, the NCBI sequence database, and our metagenomics sequence database. More...

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
(2414)
Full
(25597)
Representative proteomes NCBI
(96601)
Meta
(2712)
RP15
(2975)
RP35
(8467)
RP55
(11049)
RP75
(13545)
Jalview View  View  View  View  View  View  View  View 
HTML View    View           
PP/heatmap 1   View           
Pfam viewer View  View             

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

Key: ✓ available, x not generated, not available.

Format an alignment

  Seed
(2414)
Full
(25597)
Representative proteomes NCBI
(96601)
Meta
(2712)
RP15
(2975)
RP35
(8467)
RP55
(11049)
RP75
(13545)
Alignment:
Format:
Order:
Sequence:
Gaps:
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
(2414)
Full
(25597)
Representative proteomes NCBI
(96601)
Meta
(2712)
RP15
(2975)
RP35
(8467)
RP55
(11049)
RP75
(13545)
Raw Stockholm Download   Download   Download   Download   Download   Download   Download   Download  
Gzipped 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.

External links

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 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 View help on the curation process

Seed source: Reference 1
Previous IDs: LRR;
Type: Repeat
Author: Bateman A
Number in seed: 2414
Number in full: 25597
Average length of the domain: 23.30 aa
Average identity of full alignment: 33 %
Average coverage of the sequence by the domain: 5.68 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 20.6 9.3
Trusted cut-off 20.6 9.3
Noise cut-off 20.5 9.2
Model length: 22
Family (HMM) version: 28
Download: download the raw HMM for this family

Species distribution

Sunburst controls

Show

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...

Loading sunburst data...

Tree controls

Hide

The tree shows the occurrence of this domain 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.

Interactions

There are 13 interactions for this family. More...

Cadherin VWA RabGGT_insert E1_DerP2_DerF2 Tap-RNA_bind RnaseA LRR_adjacent LRR_1 Trypsin I-set TIG Sema LRRNT

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_1 domain has been found. There are 82 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...