YscYop

YscYop is a fictional protein complex used in speculative biology and science fiction to describe a hypothetical fusion of components from the Yersinia type III secretion system (T3SS). The name combines Ysc, the core secretion scaffold, with Yop, the family of effector proteins injected into host cells.

In this conceived model, YscYop functions as a single modular unit that assembles into a secretion apparatus capable of delivering Yop effectors directly into eukaryotic cells, thereby altering cytoskeletal dynamics and signal transduction.

In origin, the term arose in educational simulations and SF-adjacent biology writings to illustrate principles of multi-subunit complexes, translocation, and host-pathogen interactions. The hypothetical structure is typically described as having a basal body anchored in the bacterial inner membrane, a needle-like translocation apparatus, and a Yop-effector module that is activated upon host contact. The translocation signals are depicted as short N-terminal motifs recognized by the secretion machinery.

The translocation signals are depicted as short N-terminal motifs recognized by the secretion machinery.

Applications in fiction and pedagogy focus on systems biology concepts such as protein-protein interactions, mutational analysis, and the ethics and biosafety of virulence factors. No empirical evidence supports the existence of YscYop in real organisms; it is not recognized as a bona fide biological entity.

See also: Yersinia, Type III secretion system, Yop proteins, bacterial secretion.