Major latex proteins/ripening related proteins

Subclass of several proteins belonging to the Bet v 1 protein family. The "major latex proteins" were originally isolated and characterized from the latex sap of poppy plants (Papaver somniferum). Homologous genes have also been identified in non-latex-producing plants such as the tobacco plant (Nicotiana tabacum), in the pepper (Capsicum annuum), the strawberry (Fragaira vesca), the raspberry (Rubus idaeus) in the melon (Cucumis melo) and others.

The Bet v-1 family contains 11 subfamilies. The MLP/RRP subfamily belongs to these subfamilies. Protein representatives of the MLP/RRP subfamily seem to be induced during the ripening (ripenig) of fruits (e.g. paprika, melon, raspberry, strawberry) as well as during injuries (e.g. paprika). In individual plants (Arabidopsis thaliana) analogous proteins have also been found in the root area. The function of these proteins is unclear.

The only allergenic representative of the MLP/RRP subfamily is the kiwi fruit allergen Act d 11, which can be detected in about 10% of kiwi-sensitized persons.

1. Chruszcz M et al (2013) Structural and bioinformatic analysis of the kiwifruit allergen Act d 11, a member of the family of ripening-related proteins. Mol immunol 56:794-803.
2. D'Avino R et al (2011) Kiwifruit Act d 11 is the first member of the ripening-related protein family identified as an allergen. Allergy 66:870-877.