Altered development of the multicellular alga Volvox carteri caused by lectin binding

Abstract Three specific developmental processes exhibited by Volvox carteri are altered by the binding of the lectin concanavalin A: a. The commitment of the multipotent asexual reproductive cells to sexual embryogenesis is blocked by lectin binding, in both wild type female strain,where sexual development is normally induced by a specific glycoprotein sex hormone, and a spontaneously derived constitutively sexual mutant strain. b. Lectin binding blocks the process of embryo inversion, which involves coordinate changes in cell shape. c. The maintenance of stable terminal somatic cell differentiation in two mutant strains is affected by lectin binding, leading to somatic cell de-differentiation and regeneration of reproductive cells. The pleiotropic effect of lectin binding may result from modulation of cell surface receptor distribution, and implicates membrane mediated control of development and differentiation in this multicellular alga.