SUPERFAMILY 1.75 HMM library and genome assignments server

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PHL pollen allergen superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   All beta proteins [ 48724] (174)
Fold:   C2 domain-like [ 49561] (5)
Superfamily:   PHL pollen allergen [ 49590]
Families:   PHL pollen allergen [ 49591] (2)

Superfamily statistics
Genomes (229) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 3,568 6,818 2
Proteins 3,500 6,736 2

Functional annotation
General category Other
Detailed category Unknown function

Function annotation of SCOP domain superfamilies

Arabidopsis Plant Ontology (AP)

(show details)
AP termFDR (all)SDAP levelAnnotation (direct or inherited)
Plant ANatomical entity (PAN)root system0.1575Least InformativeInherited
Plant ANatomical entity (PAN)cardinal part of multi-tissue plant structure0.6407Least InformativeInherited
Plant ANatomical entity (PAN)root tip0.0000969InformativeDirect
Plant ANatomical entity (PAN)lateral root0.000001839Highly InformativeDirect

Document: AP annotation of SCOP domains

InterPro annotation
Cross references IPR007117 SSF49590 Protein matches

Expansins are unusual proteins that mediate cell wall extension in plants [PubMed7568110]. They are believed to act as a sort of chemical grease, allowing polymers to slide past one another by disrupting non-covalent hydrogen bonds that hold many wall polymers to one another. This process is not degradative and hence does not weaken the wall, which could otherwise rupture under internal pressure during growth.

Sequence comparisons indicate at least four distinct expansin cDNAs in rice and at least six in Arabidopsis. The proteins are highly conserved in size and sequence (75-95% amino acid sequence similarity between any pairwise comparison), and phylogenetic trees indicate that this multigene family formed before the evolutionary divergence of monocotyledons and dicotyledons [PubMed7568110]. Sequence and motif analyses show no similarities to known functional domains that might account for expansin action on wall extension. It is thought that several highly-conserved tryptophans may function in expansin binding to cellulose, or other glycans. The high conservation of the family indicates that the mechanism by which expansins promote wall extensin tolerates little variation in protein structure.

Grass pollens, such as pollen from timothy grass, represent a major cause of type I allergy [PubMed7930302]. Interestingly, expansins share a high degree of sequence similarity with the Lol p I family of allergens. This entry represents the C-terminal domain.

InterPro database

PDBeMotif information about ligands, sequence and structure motifs
Cross references PDB entries
Ligand binding statistics
Nucleic-acid binding statistics
Occurrence of secondary structure elements
Occurrence of small 3D structural motifs

PDBeMotif resource

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Arabidopsis Plant Ontology (AP) ]

Internal database links

Browse genome assignments for this superfamily. The SUPERFAMILY hidden Markov model library has been used to carry out SCOP domain assignments to all genomes at the superfamily level.

Alignments of sequences to 4 models in this superfamily are available by clicking on the 'Alignments' icon above. PDB sequences less than 40% identical are shown by default, but any other sequence(s) may be aligned. Select PDB sequences, genome sequences, or paste in or upload your own sequences.

Browse and view proteins in genomes which have different domain combinations including a PHL pollen allergen domain.

Examine the distribution of domain superfamilies, or families, across the major taxonomic kingdoms or genomes within a kingdom. This gives an immediate impression of how superfamilies, or families, are restricted to certain kingdoms of life.

Explore domain occurrence network where nodes represent genomes and edges are domain architectures (shared between genomes) containing the superfamily of interest.

There are 4 hidden Markov models representing the PHL pollen allergen superfamily. Information on how the models are built, and plots showing hydrophobicity, match emmission probabilities and insertion/deletion probabilities can be inspected.

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Arabidopsis Plant Ontology (AP) · Internal database links ]