acrasin

noun

acra·​sin ə-ˈkrā-sᵊn 

plural acrasins

: a substance (such as cyclic AMP) that is secreted by myxamoebae of various cellular slime molds (such as those of the genus Dictyostelium or Acrasis) and that functions as a chemotactic agent attracting and causing the aggregation of similar amoeboid cells into a pseudoplasmodium

The cells are not only oriented by … acrasin, but induced to secrete it; they thus relay the orienting signals.

—B. M. Shaffer, Nature, 12 June 1975

Word History

Etymology

New Latin Acrasiales acrasiales + -in entry 1

First Known Use

1947, in the meaning defined above

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