New binding specificities evolve via point mutation in an invertebrate allorecognition gene.

ABSTRACT: Many organisms use genetic self-recognition systems to distinguish themselves from conspecifics. In the cnidarian, Hydractinia symbiolongicarpus, self-recognition is partially controlled by allorecognition 2 (Alr2). Alr2 encodes a highly polymorphic transmembrane protein that discriminates self from nonself by binding in trans to other Alr2 proteins with identical or similar sequences. Here, we focused on the N-terminal domain of Alr2, which can determine its binding specificity. We pair ancestral sequence reconstruction and experimental assays to show that amino acid substitutions can create sequences with novel binding specificities either directly (via one mutation) or via sequential mutations and intermediates with relaxed specificities. We also show

SUBMITTER: Huene AL 

PROVIDER: S-EPMC8282982 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature