  Membrane deformation inside living cells is crucial for the proper shaping of
various intracellular organelles and is necessary during the fission/fusion
processes that allow membrane recycling and transport (e.g. endocytosis).
Proteins that induce membrane curvature play a key role in such processes,
mostly by adsorbing to the membrane and forming a scaffold that deforms the
membrane according to the curvature of the proteins. In this paper we explore
the possibility of membrane tube destabilisation through a pearling mechanism
enabled by the combined effects of the adsorbed curved proteins and the actin
polymerization they may recruit. The pearling instability can furthermore serve
as the initiation for fission of the tube into vesicles. We find that adsorbed
proteins are more likely to stabilise the tubes, while the actin polymerization
can provide the additional constrictive force needed for the robust
instability. We discuss the relevance of the theoretical results to in-vivo and
in-vitro experiments.
