AF069: Bet v 1 family

List allergens from this family:

Routes of exposure:
Include only IUIS approved allergens.

Biochemical properties

Bet v 1-related proteins are widely distributed among vascular plants. The family was classified by sequence similarity into two large and several small subfamilies showing low levels of sequence identity but conserved structures [1]. The largest of these is the pathogenesis-related protein family PR-10 [2]. The expression of these proteins is either induced by pathogen attack or abiotic stress or developmentally regulated. PR-10 proteins are expressed in high concentrations in reproductive tissues such as pollen, seeds and fruits. The biochemical function of most PR-10 proteins is unknown. For some PR-10 subfamily members an enzymatic function as ribonuclease [3] or oxidative coupling enzyme involved in biosynthesis of secondary metabolites was shown [4]. Like all members of the Bet v 1-family, PR-10 proteins contain a large ligand-binding cavity that can accommodate diverse ligands including plant steroids [5], cytokinins [6] and flavonoids [7]. The other large subfamily is a group of major latex proteins and ripening-related proteins (MLP/RRP) first described in the latex of opium poppy [8]. Their biologic function is unknown, but they appear to have a role in defense against biotic and abiotic stress [9].

Allergens from this family

The major birch pollen allergen, Bet v 1, is a member of the PR-10 family. Closely-related, cross-reactive allergens were found in the pollen of other trees from the order Fagales such as hazel, alder, oak and chestnut. Many birch pollen-allergic patients show allergic reactions to various fruits and vegetables, which are caused by IgE cross-reactivity between Bet v 1 and homologous allergens from plant foods [10]. Most Bet v 1-related food allergens were found in members of certain plant families: Rosaceae (apple, pear, stone fruits), Apiaceae (celery, carrot), and Fabaceae (soybean, peanut). Only two Bet v 1-related allergens were identified outside the PR-10 subfamily. Vig r 6 is a minor allergen from mung bean and member of the cytokinin-specific binding proteins subfamily, a small subfamily distantly related to the PR-10 group [11]. Act d 11 is a minor kiwifruit allergen belonging to the MLP/RRP subfamily [12].



  1. Radauer C, Lackner P, Breiteneder H:
    The Bet v 1 fold: an ancient, versatile scaffold for binding of large, hydrophobic ligands.
    BMC Evol Biol 2008, 8, 286. [PubMed] [Full Text]
  2. Fernandes H, Michalska K, Sikorski M, Jaskolski M:
    Structural and functional aspects of PR-10 proteins.
    FEBS J 2013, 280, 1169-99. [PubMed] [Full Text]
  3. Park CJ, Kim KJ, Shin R, Park JM, Shin YC, Paek KH:
    Pathogenesis-related protein 10 isolated from hot pepper functions as a ribonuclease in an antiviral pathway.
    Plant J 2004, 37, 186-98. [PubMed]
  4. Michalska K, Fernandes H, Sikorski M, Jaskolski M:
    Crystal structure of Hyp-1, a St. John's wort protein implicated in the biosynthesis of hypericin.
    J Struct Biol 2010, 169, 161-71. [PubMed] [Full Text]
  5. Markovic-Housley Z, Degano M, Lamba D, von Roepenack-Lahaye E, Clemens S, Susani M, Ferreira F, Scheiner O, Breiteneder H:
    Crystal structure of a hypoallergenic isoform of the major birch pollen allergen Bet v 1 and its likely biological function as a plant steroid carrier.
    J Mol Biol 2003, 325, 123-33. [PubMed]
  6. Sliwiak J, Dolot R, Michalska K, Szpotkowski K, Bujacz G, Sikorski M, Jaskolski M:
    Crystallographic and CD probing of ligand-induced conformational changes in a plant PR-10 protein.
    J Struct Biol 2016, 193, 55-66. [PubMed] [Full Text]
  7. Seutter von Loetzen C, Hoffmann T, Hartl MJ, Schweimer K, Schwab W, Rosch P, Hartl-Spiegelhauer O:
    Secret of the major birch pollen allergen Bet v 1: identification of the physiological ligand.
    Biochem J 2014, 457, 379-90. [PubMed] [Full Text]
  8. Osmark P, Boyle B, Brisson N:
    Sequential and structural homology between intracellular pathogenesis-related proteins and a group of latex proteins.
    Plant Mol Biol 1998, 38, 1243-6. [PubMed]
  9. Chen JY, Dai XF:
    Cloning and characterization of the Gossypium hirsutum major latex protein gene and functional analysis in Arabidopsis thaliana.
    Planta 2010, 231, 861-73. [PubMed] [Full Text]
  10. Vieths S, Scheurer S, Ballmer-Weber B:
    Current understanding of cross-reactivity of food allergens and pollen.
    Ann N Y Acad Sci 2002, 964, 47-68. [PubMed]
  11. Guhsl EE, Hofstetter G, Hemmer W, Ebner C, Vieths S, Vogel L, Breiteneder H, Radauer C:
    Vig r 6, the cytokinin-specific binding protein from mung bean (Vigna radiata) sprouts, cross-reacts with Bet v 1-related allergens and binds IgE from birch pollen allergic patients' sera.
    Mol Nutr Food Res 2014, 58, 625-34. [PubMed] [Full Text]
  12. D'Avino R, Bernardi ML, Wallner M, Palazzo P, Camardella L, Tuppo L, Alessandri C, Breiteneder H, Ferreira F, Ciardiello MA, Mari A:
    Kiwifruit Act d 11 is the first member of the ripening-related protein family identified as an allergen.
    Allergy 2011, 66, 870-7. [PubMed] [Full Text]


Links to Pfam

Family-defining Pfam domains (at least one of these domains is present in each family member):

Pfam domain Pfam clan
PF00407 Pathogenesis-related protein Bet v I family CL0209 Bet V 1 like

Links to Wikipedia


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