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INTRODUCTION
1. Rationale
In gravitational biology, studies of microgravity in space have
shown many effects of gravity conditions on biological processes,
gravity-sensitive mechanisms, or the gravity-based orientation of
organisms. However, research in space has encountered a number of
difficulties, including expensive research facilities and negative
effects of microgravity on astronauts. To overcome the above
difficulties, scientists have developed biological system models that
simulate conditions similar to the microgravity in space for further
gravitational studies on living organisms.
Many studies showed that cells in different organisms behave
differently in space than they do on Earth. Due to the great diversity
of cell types in nature, the effects of microgravity on those cells are
extremely diverse and often complex. Some studies on the role of
microgravity in cell proliferation and differentiation have
demonstrated that cells that grow in microgravity develop differently
than under normal conditions, leading to notable changes in cell
division. Cytoskeleton is also one of the most affected structure
under microgravity. The cytoskeleton forms the main structure of the
cell and includes interactions between microtubules, actin
microfibers, intermediate microfibers and related proteins. Hence,
the cytoskeleton is very much related to the cell shape.
Abnormalities in the organization of microtubules and microfibers in
the cytoskeleton can have a detrimental effect on the cell itself, even
with very large consequences when the cell is in the embryonic
stage. The mechanisms of proliferative and cytoskeletal structural
changes under microgravity have not been clearly demonstrated yet.
