  According to the recent proposal by Aharony, Bergman, Jafferis and Maldacena
the N=6 supersymmetric Chern-Simons theory in three dimensions has a 't Hooft
limit whose holographic dual is described by type IIA superstings on AdS_4 x
CP^3 background. We argue that the Green-Schwarz action for type IIA string
theory on AdS_4 x CP^3 with kappa-symmetry partially fixed can be understood as
a coset sigma-model on the same space supplied with a proper Wess-Zumino term.
We construct the corresponding sigma-model Lagrangian and show that it is
invariant under a local fermionic symmetry which for generic bosonic string
configurations allows one to remove 8 out of 24 fermionic degrees of freedom.
The remaining 16 fermions together with their bosonic partners should describe
the physical content of AdS_4 x CP^3 superstring. As further evidence, we
demonstrate that in the plane-wave limit the quadratic action arising from our
model reproduces the one emerging from the type IIA superstring. The coset
sigma-model is classically integrable which opens up the possibility to
investigate its dynamics in a way very similar to the case of AdS_5 x S^5
superstrings.
