Editors' ChoiceImmunology

Self-Defense in the Spineless

Science's STKE  13 Jul 2004:
Vol. 2004, Issue 241, pp. tw256
DOI: 10.1126/stke.2412004tw256

A hallmark of the vertebrate immune system is the ability to generate a huge repertoire of distinct antigen receptors through somatic shuffling of immune receptor gene segments. Although invertebrates also have proteins encoded by members of the immunoglobulin superfamily (IgSF), it has not so far been apparent that they have evolved similar means of generating receptor diversity. Exploring the immune defenses in a species of snail, Zhang et al. uncovered diverse IgSF genes, termed fibrinogen-related protein (FREP) genes. Closer scrutiny revealed FREP diversity to be generated by point mutation and by a process similar to gene conversion--two mechanisms that help to generate antibody diversity in vertebrates.

S.-M. Zhang, C. M. Adema, T. B. Kepler, E. S. Loker, Diversification of Ig superfamily genes in an invertebrate. Science 305, 251-254 (2004). [Abstract] [Full Text]